tx21 (metadex) rounding clarification resulting from conversation with Marv
Better clarification of rounding after dexx reminded me of earlier conversation in issue #170
Fix markdown formatting
Prices never move!!

This was decided awhile back, but I couldn't find it in the spec.
All orders are sell orders!

This was already in the spec, but not clear enough, per chatroom.
typo
Merge pull request #289 from dacoinminster/tx21clarification

tx21 (metadex) rounding clarification