D code accepts fanuc varibles, not constants
GCode renamed to FanucMacro, it's a proper name
G names in modules comprising are replaced with F names
interpreter modules renamed, all is ready for FInterpreter development
added G prefix to types describing GCode
Fanuc macro interpreter sketch
skeleton of FInterpreter is ready, passes a trivial test
some renames
test files renamed
Better comment handling

Previously implemented scheme involving delaying last operator output replaced with a simpler one. Operators are generated immediately, comments are implemented in a similar way as code blocks were by censoring RWS monad.

This allowed to support both inline and standalone comments
fixed GExpr generator which was damaged by automatic renaming s/ G/ F/
modules reorganized into a hierarchy