Do not hardcode composer checksum

This allows composer installs to function even if the installer checksum
changes, and doesn't force us to update the formula whenever their
installer changes.

We can do this now as composer upstream provides the checksum on
https://composer.github.io/installer.sig since 2016-04-28.

Update php ng map with debian php 7.0

Explicitly set HOME when running composer install.

Add default pools values

Without this installation fails with:

  The HOME or COMPOSER_HOME environment variable must be set for
  composer to install correctly

minor improvements to archlinux php cli.

Add opcache package for CentOS

Update composer installer sha256 hash

Added the readline PHP package and added support for installing PHP7 …

Run composer installer with PHP

The composer installer has to be executed with PHP itself as detailed on
https://getcomposer.org/download/.

Only add ppa if it doesn't exist.

This comit is in addition to pull request #70. The add-apt-repository command
will only be run when the ppa has not yet been added.

Added the php-mail package for Debian

Manually add php PPA in UTF-8 locale [Resolves #69]

changed Debian hhvm PID filepath to match default /etc/init.d/hhvm PID filepath

manage xcache.ini in pillar

use False as default, and test boolean, rather than none

Sort keys per section within php.ini.

alphabetically

Fix install-composer edge cases

Recursively merge php.ini options

Add hhvm support to php ng formula

In order to reuse the default structure of this formula
I changed the config a little bit to configure hhvm files.

Fix Debian package name for `php.ng.xml` state

Update Composer state file to not use curl

Add support for GMP ext