Support sending email when there is not a current_user
Update caller specs to AssignmentManager
Add AssignmentManager to control when to add participants during task assignee changes
Merge pull request #475 from Tahi-project/create-participant-on-task-addition-v2

Create participant on task addition
:raised_hands: Add support for multiple sidekiqs

This is so we can have iHat and tahi running on the same machine
without one sidekiq fighting over the other.

Make sure to have REDIS_PROVIDER set in your .env
Merge pull request #478 from Tahi-project/support-multiple-sidekiqs

:raised_hands: Add support for multiple sidekiqs
Merge branch 'master' into fix-phase-header-positioning