This PR makes it possible to run the test suite using the included autoloader, as opposed to forcing composer to be present. It does a promenant message reminding people that the ideal way to run the test suite is after going a "composer install", but seeing that Stash has no external dependancies it still runs the tests.
Updated Autoloader to work with Test suite.
Stash is located in '/src', while the test suite is in '/tests'. The
provided autoloader only supported '/src' which made testing without
Updated test bootstrapper to fall back to included autoloader
In the event that composer is not present, the test suite will fall
back to the provided autoloader. As part of this change the message for
when "composer install" hasn't been run has been made more predominate.