Updated the join open group method to retrieve the capabilities as part of the initial request
Updated the OpenGroupManager to require a transaction to be passed to the various 'handler' methods (allowing for everything to be processed within a single transaction)
Fixed a few issues where we weren't storing the timestamp for open group messages and DMs which could result in duplicate messages
Fixed an issue where we were setting the timestamp value for messages sent to an open group without converting it to be milliseconds to be consistent with other messages
Fixed an issue where the BatchRequestInfo could incorrectly flag it's response as failing to parse even though the type was optional
Fixed a bug where the open group would re-fetch all messages every other time
Fixed a bug where the long press context menu wouldn't appear after failing to delete a message
Fixed a bug where joining an open group would trigger the join behaviour and APIs twice
Added a few types to make the code more readable
Added the inbox request to the polling
Added a couple of properties to the TSContactThread to indicate the originating open group to support SOGS DMs
Added code to store the latest message id for an open group inbox
Added a bunch of documentation from the API docs into the OpenGroupAPI (and associated models)
Updated the OpenGroupAPI to match the latest docs
Fixed the incorrect structure of the SendDirectMessageRequest
Fixed an incorrect inbox endpoint path
Tweaked the batch response handling so it wouldn't fail to parse all responses if a single one failed
Renamed IdPrefix to SessionId.Prefix and cleaned up the type to be more readable & self-documenting
Added the MessageRequestsViewController
Added a 'Message Requests' button to the settings screen
Added accept/reject buttons for message requests to the ConversationVC
Added the ability to hide the message request item on the HomeVC (re-appears if you get a new message request)
Added code to handle an edge-case where the message request approval state wouldn't be returned to the sender due to the recipient running an old version of the app
Prevented contacts which aren't associated with an approved thread from appearing when creating a closed group
Disabled notifications for threads which aren't approved
Updated the app notification count to exclude unapproved messages
Updated the app to ignore closed group creation messages if the group has no admins which are approved contacts
Fixed up the keyboard avoidance behaviour in the ConversationVC
Fixed a couple of minor interaction issues which affected some devices
Fixed an issue where the database migrations would run on the 2nd launch when creating a new account (causing odd behaviours)
