Several changes to fix and facilitate running phpunit tests
- phpunit now in composer.json (under require-dev).
- added some pathes to bootstrap.php so it looks for classes in vendor
- added some 'use' statements in some test files that needed them.

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@47779 b456876b-0849-0410-b77d-98878d47e9d5