* [bugfix] Fix unicode-unaware word boundary check in hashtag regex
Go `\b` does not care for Unicode, and without lookahead, the workarounds got
very ugly. So I replaced the regex with a parser.
The parser runs in O(n) time and performance should not be affected.
* [bugfix] Add back hashtag max length and add tests for it
* remove mention util function from db
* add ParseMentionFunc to gtsmodel
* add parseMentionFunc to processor
* refactor search to simplify it a bit
* add parseMentionFunc to account
* add parseMentionFunc to status
* some renaming for clarity
* test dereference of unknown mentioned account
Inbox POST from federated servers now working for statuses and follow requests.
Follow request client API added.
Start work on federating outgoing messages.
Other fixes and changes/tidying up.