Add Russian GOST layouts
Add two Russian layouts defined in the state GOST standards:
- 6431-75 (amended) for typewriters,
- 14289-88 (amended) for computers.
Probably, not widely used (so they go in extra) but the standards are still in force. The 14289-88 version also provides some useful symbols missing from "Russian (typewriter)".
Edited by homocomputeris