JOINDIN-439 Add phpcs task to the build file
JOINDIN-439 Fix the issues found by codesniffer
Error checking for event model
Also some whitespace fixes in the test file, and adding a missing getter test
Fix documentation so that it refers to Redis, and not MongoDB
no message
Fix grammar for "I"m attending" button
Now takes into account whether or not it's a past event
Rename method to get API url to mark as attending
Add website address to event page
adding some onboarding instructions to the about page
Merge branch 'master' into JOINDIN-439

Conflicts:
	app/Joindin/Model/Event.php
making the dates display in comments
Merge branch 'clairs-event-model-error-checking'
Merge branch 'clairs-doc-update-redis'
Merge branch 'master' into clairs-cleanup-event-model and handle
conflicts between multiple changes on the same code

Conflicts:
	tests/Model/EventTest.php
Merge branch 'clairs-cleanup-event-model'
Move files around
Update use of namespaces in files
Remove ConfigHelper as it's only used in one place: the base controller.
Implement BaseDb for consistency with BaseController and BaseApi
slugify twig filter isn't actually used