Add invite model
Add invites controller
Add invite link to header
Add invite methods to users
Add route to post to
Add invites index page to display invites
Fix invite creation method
Add invite mailer
Add template for invite email
Edits to invite mailer and invites controller
Give people access to making invite codes
Change text on the invites page
Merge pull request #515 from teamleada/mark-invite-system

Invite system