Fix notice-level error when cache not configured
Merge pull request #435 from shaneiseminger/master

Fix notice-level error when cache not configured
The PHPUnit XML file is a default distributed one,
so should be marked as such
Setting strict defaults to test how far we can push
the testing...
Updating the Travis script to run the correct config
Adding the non-distributed `phpunit.xml` file to
the `.gitignore`
Merge pull request #437 from Rican7/feature/phpunit-hardening

Feature - PHPUnit hardening
Use absolute import path for Relationship.php

closes #447
Merge pull request #448 from jpfuentes2/jpfuentes2/use_absolute_require

Use absolute import path for Relationship.php
fix find by null