Adds a CTA on the room list to view invites if there are any.
The invite list presents each invite with accept/decline buttons
and (for room invites) the sender details.
Fixes#102
* Validate ids in constructors.
* Remove redundant `.value` usage in string interpolation.
* Make a distinction between `SessionId` and `UserId` in `TestData`.
* Design fixes.
* Make text in emoji items secondary color and the snackbar duration short again
* Try to make margins smaller on smaller displays
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Co-authored-by: Florian Renaud <florianr@element.io>
* Create `RoomLastMessageFormatter` to produce readable room summaries.
* Add unit tests using Robolectric, fix bugs
* Add changelog
* Move `RoomLastMessageFormatter` back to `impl` module, allow it to receive an `EventTimelineItem` instead of `MessageContent`.
