Refactor {mock,fixture}_test out to test package
Refactor fixture_test out to test/w
Refactor watcher_test to use test package
Refactor watcher_inotify_test to use test package
Remove no longer needed fixture_test and mock_test
Fix missing imports for watcher_inotify_test
Refactor watcher_fsnotify test to use test package
Inline package doc for test
Fix for race under Linux

https://travis-ci.org/yaey8Hee/Oong7Pha/jobs/37063407