Massive update for persistent connections NOTE: persistent connections are now OPTIONAL. This is EXTREMELY important because PHP's persistent connection handler is broken in all current builds of PHP, including 5.6 STABLE, 7.0 STABLE, 7.1 BETA, and 7.2 HEAD Pull request for PHP can be found here: https://github.com/php/php-src/pull/2195

Added Travis CI support for automatic continuous integration unit testing. This is built around PUDL's existing testing frame work. Some minor tweaks were added to make it Travis CI compatible.

Fixed legacy support for PHP 5.4. This is NOT officially supported platform, however it was a simple function call change that needed updating to at least validate the unit tests on PHP 5.4

Other minor fixes too (typos, using variables which are optionally defined, things like this)