Changing submatching syntax from "->" to ":"  and M, MA to be shorthand for ($m:_M):1 and ($m:_M):2, respectively.
Also, "M" is optional if followed by ":", "M:1" is same as ":1"

Also, adding M in grammar to be shorthand for $m:_M (vargetter) op in match context.

MatchVector, AnnotationMatch, TokenMatch are now MatchData
MatchData is value_type of Match which now has get_value/set_value
Match has also copy construction working properly now
Default value for Match holds MatchVector so adding $m:_M var in grammar works as intended.

The prefix like "$m:" signifies type in WCCL, but in Variables code it comes from template argument; in this particular example, the <Match> type.