jslint & whitespace on pre-commit

pre-commit

#!/bin/sh -e

if git rev-parse --verify HEAD >/dev/null 2>&1
then
	against=HEAD
else
	# Initial commit: diff against an empty tree object
	against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

# Check whitespace
git diff-index --check --cached $against --

# JSLINT (https://github.com/ConradIrwin/jslint-node)
jslint --ignore-no-files `git diff-index --name-only $against -- | grep '\.js$'`