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.
Yeah, I saw it was in our validators like that. They should probably be fixed to properly use the i18n message parameters than doing our own replacements, but that can be a low-priority task for later.