Message fixes
- Do not load first conversation on loading full page message view: Apparently this wasn't the old behaviour because it was overwritten by some weird behaviour. There is complaints that people don't want the newest conversations marked read after clicking on messages.
- Disallow creating conversations with non-existing users
- Add buddy relationship to seed data to play locally with message composer people choser
- add back the IDs of people when starting a group chat to the search results
- (small feature...) allow finding people by typing their ID into the recipient list