User roles
Can ask if a user has multiple roles
Check required_roles against user in Ability#can?
Only show subforums that the user's roles permit
WIP: fix tests
Fix user role tests
Require roles to see threads
Pull subforum required roles query into method
Use a scope instead of a method
Fix post test
Set roles when creating/updating users
Make user admin if they are HS faculty
Give faculty all roles
Fix user roles migration
Multiline block goes in do/end
has_roles? => satisfies_roles?
Include reply_info as a Mailgun variable
Hard line breaks in Markdown rendering

Closes #143
Include guard against broadcasting a post with no groups
Don't print stacktrace in broadcast guard

It won't be useful since it's running in a job.