* Update annotate to version 2.7.3
* Update aws-sdk-s3 to version 1.9.2
* Update browser to version 2.5.3
* Update capistrano to version 3.10.2
* Update domain_name to version 0.5.20180417
* Update http to version 3.2.0
* Update lograge to version 0.10.0
* Update oj to version 3.5.1
* Update parallel_tests to version 2.21.3
* Update puma to version 3.11.4
* Update rubocop to version 0.55.0
* Update scss_lint to version 0.57.0
* Update simplecov to version 0.16.1
* Update tty-command to version 0.8.0
* Update tty-prompt to version 0.16.0
* Update pkg-config to version 1.3.0
* Update fog-local to version 0.5.0
* Update fog-openstack to version 0.1.25
* Update devise-two-factor to version 3.0.3
* bundle update
* Add consumable invites
* Add UI for generating invite codes
* Add tests
* Display max uses and expiration in invites table, delete invite
* Remove unused column and redundant validator
- Default follows not used, probably bad idea
- InviteCodeValidator is redundant because RegistrationsController
checks invite code validity
* Add admin setting to disable invites
* Add admin UI for invites, configurable role for invite creation
- Admin UI that lists everyone's invites, always available
- Admin setting min_invite_role to control who can invite people
- Non-admin invite UI only visible if users are allowed to
* Do not remove invites from database, expire them instantly
