.htaccess performance and other improvements

.htaccess

# Increase the memory usage.
# If you get an error after adding this, try 64M or 32M instead.
php_value memory_limit "128M"

# Add syntax highlighting
AddType application/x-httpd-php-source .phps

# JavaScript
#   Normalize to standard type (it's sniffed in IE anyways)
#   tools.ietf.org/html/rfc4329#section-7.2
AddType application/javascript              js

# Audio
AddType audio/ogg                           oga ogg
AddType audio/mp4                           m4a

# Video
AddType video/ogg                           ogv
AddType video/mp4                           mp4 m4v
AddType video/webm                          webm

# SVG
#   Required for svg webfonts on iPad
#   twitter.com/FontSquirrel/status/14855840545
AddType     image/svg+xml                   svg svgz
AddEncoding gzip                            svgz

# Webfonts
AddType application/vnd.ms-fontobject       eot
AddType application/x-font-ttf              ttf ttc
AddType font/opentype                       otf
AddType application/x-font-woff             woff

# Assorted types
AddType image/x-icon                        ico
AddType image/webp                          webp
AddType text/cache-manifest                 appcache manifest
AddType text/x-component                    htc
AddType application/x-chrome-extension      crx
AddType application/x-opera-extension       oex
AddType application/x-xpinstall             xpi
AddType application/octet-stream            safariextz
AddType application/x-web-app-manifest+json webapp
AddType text/x-vcard                        vcf

# Use UTF-8 encoding for anything served text/plain or text/html
AddDefaultCharset utf-8

# Force UTF-8 for a number of file formats
AddCharset utf-8 .css .js .xml .json .rss .atom

# BEGIN Block directory browsing
<IfModule mod_autoindex.c>
  Options -Indexes
</IfModule>
# END Block directory browsing

# Don't allow access to .htaccess
<Files .htaccess>
deny from all
</Files>
IndexIgnore .htaccess */.??*

# Default Language
DefaultLanguage en-GB

# BEGIN Enable Gzip
# Best and easiest form of optimisation - sacrifice CPU cycles to encode for much smaller data transfer - well worth it.
# Don't gzip images - they are already compressed.
# For even more benefit, write alphabetical CSS key:value pairs and HTML attributes! (Google saved about 1.5% data transfer by doing this)
<IfModule mod_deflate.c>
  <IfModule mod_setenvif.c>
  
    # Force deflate for mangled headers developer.yahoo.com/blogs/ydn/posts/2010/12/pushing-beyond-gzipping/
    <IfModule mod_headers.c>
      SetEnvIfNoCase ^(Accept-EncodXng|X-cept-Encoding|X{15}|~{15}|-{15})$ ^((gzip|deflate)\s*,?\s*)+|[X~-]{4,13}$ HAVE_Accept-Encoding
      RequestHeader append Accept-Encoding "gzip,deflate" env=HAVE_Accept-Encoding
    </IfModule>
    
      BrowserMatch ^Mozilla/4 gzip-only-text/html
      BrowserMatch ^Mozilla/4\.0[678] no-gzip
      BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
      BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html
  </IfModule>
  <IfModule mod_headers.c>
      Header append Vary User-Agent env=!dont-vary
  </IfModule>
  AddOutputFilterByType DEFLATE text/css application/javascript text/html text/richtext image/svg+xml text/plain text/xsd text/xsl text/xml
  <FilesMatch "\.(ttf|otf|eot|svg)$" >
    SetOutputFilter DEFLATE
  </FilesMatch>
</IfModule>
# END Enable Gzip

# BEGIN Expire headers
# Makes cached files stay cached for longer (304 Not modified) = fewer 200 responses.
# Aim for at least 1 month for images, ideally a year (not longer - that'll break RFC specs)
<IfModule mod_expires.c>
  ExpiresActive On
  ExpiresDefault                              "access plus 1 month"
  ExpiresByType image/*                       "access plus 1 year"
  ExpiresByType video/*                       "access plus 1 year"
  ExpiresByType application/x-shockwave-flash "access plus 1 year"
  ExpiresByType text/css                      "access plus 1 year"
  ExpiresByType application/javascript        "access plus 1 year"
  ExpiresByType application/x-font-ttf        "access plus 2 months"
  ExpiresByType font/opentype                 "access plus 2 months"
  ExpiresByType application/x-font-woff       "access plus 2 months"
  ExpiresByType image/svg+xml                 "access plus 2 months"
  ExpiresByType application/vnd.ms-fontobject "access plus 2 months"
  ExpiresByType text/x-component              "access plus 2 months"
  ExpiresByType application/rss+xml           "access plus 1 hour"
  ExpiresByType application/atom+xml          "access plus 1 hour"
  ExpiresByType text/html                     "access plus 1 hour"
  ExpiresByType application/xhtml+xml         "access plus 1 hour"
  ExpiresByType text/cache-manifest           "access plus 0 seconds"
  ExpiresByType text/xml                      "access plus 0 seconds"
  ExpiresByType application/xml               "access plus 0 seconds"
  ExpiresByType application/json              "access plus 0 seconds"
</IfModule>
# END Expire headers

# BEGIN Cache-Control Headers
# Only using the private/public values here - not max-age (Expires headers cover the same thing, and are more widely supported)
<IfModule mod_headers.c>
  <FilesMatch "\\.(ico|pdf|flv|jpe?g|png|gif|swf|js|css|mp3|mp4|woff|eot|ttf)$">
    Header set Cache-Control "public"
  </FilesMatch>
  <FilesMatch "\\.(x?html?|txt|xml|xsl|php)$">
    Header set Cache-Control "private, must-revalidate"
  </FilesMatch>
</IfModule>
# END Cache-Control Headers

# BEGIN Turn ETags Off
# Inherently misconfigured, especially for server clusters
<IfModule mod_headers.c>
  Header unset ETag
</IfModule>
FileETag None
# END Turn ETags Off

# BEGIN Remove Last-Modified Header
# We're using Expires header to check for freshness, so save bytes by not returning this header.
<IfModule mod_headers.c>
  Header unset Last-Modified
</IfModule>
# END Remove Last-Modified Header

# BEGIN Better IE experience
# Force latest IE version, use ChromeFrame if available.
<IfModule mod_headers.c>
  Header set X-UA-Compatible "IE=Edge,chrome=1"
  # mod_headers can't match by content-type, but we don't want to send this header on *everything*...
  <FilesMatch "\.(js|css|gif|png|jpe?g|pdf|xml|oga|ogg|m4a|ogv|mp4|m4v|webm|svg|svgz|eot|ttf|otf|woff|ico|webp|appcache|manifest|htc|crx|oex|xpi|safariextz|vcf)$" >
    Header unset X-UA-Compatible
  </FilesMatch>
</IfModule>
# END Better IE Experience

# BEGIN Image WordPress Media Upload HTTP Error Fix
<IfModule mod_security.c>
  <Files async-upload.php>
    SecFilterEngine Off
    SecFilterScanPOST Off
  </Files>
</IfModule>
<IfModule security_module>
  <Files async-upload.php>
    SecFilterEngine Off
    SecFilterScanPOST Off
  </Files>
</IfModule>
<IfModule security2_module>
  <Files async-upload.php>
    SecFilterEngine Off
    SecFilterScanPOST Off
  </Files>
</IfModule>
# END Image WordPress Upload HTTP Error Fix