Add setup-tests.php and defined() checks in setup.php

+ Create setup-tests.php which defines test-specific configuration, then
  includes the root level setup.php.
+ Wrap each define() in setup.php and setup-tests.php in defined() checks.
+ Change bootstrap setting in phpunit.xml.
Fix errors introduced by auto-replace.
Merge pull request #43 from leftclickben/SetupTestsDotPhp

Add setup-tests.php and defined() checks in setup.php