-moved rc.mavlink to the boards optional rc additions (now it's called rc.board_mavlink) to handle board specific mavlink needs (mavlink over usb, ethernet, additional streams, etc.)
-mavlink module will be responsible to usb defaults, therefore less args are needed to be passed to mavlink module if one wants to use mavlink over usb.
-the way to check if connection is usb is by it's designated variable and not by config mode.
* Fixed the version tag to number and version tag to vendor version number to return dev version in case of any local modifications or in case there's a dash before firmware type in tags that support vendor version.
garfieldG