Interactive maps messages review

This pull request was created only for message review purposes. Do not merge it!

Dear ComEng developers: pick red or green background to review the messages and their documentation, please :)

Once you finish review and we address all found issues we'll be able to delete the branch.
You're referring to a user, so this should support gender. You are passing the username, but [the output format you're using in the controller is `->plain()`](https://github.com/Wikia/app/blob/245a7765/extensions/wikia/WikiaInteractiveMaps/controllers/WikiaInteractiveMapsParserTagController.class.php#L112), so `{{GENDER:}}` won't work. You need to change the output format to `->text()`.