Enhancement: Add proxy support for pear/pecl modules

[uoe-pjackson]

We are running a server in a network without direct outgoing Internet connections. Access to the internet is via an http proxy. Currently it appears that proxy is not supported for pear/pecl module only php::composer

I can see that proxy_type and proxy_server are set at the ::php class level so I may have a shot at creating a PR that uses these for pear/pecl modules.