From now OpenSAPS supports template formatting. For examples see
Gitea or Gitlab parser for creating template and data and
matrixconnection.go for how to use them.
Improved Matrix formatter - now we can do links and put repeatables
(like commits) in resulting message.
Added Gitlab parser. Incomplete, but can parse commits, issues,
merge requests, tags messages.
Refactored (a little) Gitea parser. No functional changes, still
only commits parsing.
Both Gitlab and Gitea parsers will put back a message if unknown
message type was passed.
