Updated inputs for terraform dcos-docs

dcos-docs-helper.sh

for i in ./pages/install-include/*-inputs*; do ( 
  CURDIR=${PWD}
  echo "${PWD}"/${i};
  cd ${HOME}/src/github.com/dcos-terraform/terraform-$(basename ${i} | sed -E "s/-.*//")-dcos/
  IFS=$'\n' FILES=($(egrep -H -r '^(variable \")' *.tf | cut -d: -f1 | uniq | gsed 's/:.*//'));
  for j in $FILES; do
    VARFILES="${VARFILES} ${HOME}/src/github.com/dcos-terraform/terraform-$(basename ${i} | sed -E "s/-.*//")-dcos/${j}"
  done;
  cd ${CURDIR};
  echo "Here is a list of all the variables that are currently supported on the Universal Installer and available for you to customize your cluster." > ${i}
  /bin/sh -c "terraform-docs --sort-inputs-by-required --with-aggregate-type-defaults md ${VARFILES} >> ${i}"
); done