Fixes to list behaviours in UI

Summary:
- Fix allowed_methods check on tags list (Refs T746)
- Remove select-post class used in user and tags lists
- Fix select all on tags and users lists
- Update posts list select html to match other lists (Refs T745)

Test Plan:
Go to each list (posts, users, tags)
Select and deselect items - check this works
Click select all - check this work

Reviewers: shadowhand

Reviewed By: shadowhand

Maniphest Tasks: T745, T746

Differential Revision: https://phabricator.ushahidi.com/D338