Update Nginx and associated config files to 1.4.1

Add new sources to install nginx 1.4.1 and adjust the default configuration a bit so that it works properly with this version.
Treat our php.ini as custom rather than default

As we saw with nginx and xdebug, things change in config files between releases. We should do what we can to keep our changes in smarter locations. This moves our php.ini file to a conf.d/php-custom.ini file where custom directives can be set without worrying about the overall configuration of PHP.
Remove least likely directives for custom php.ini
Remove the quick reference in custom php.ini
And keep trimming the custom php.ini
Use new fastcgi_param with default config as well
Additional custom php.ini trimming