MAI: do not import hidden `pyparsing._noncomma`, instead reconstruct it
MAI: do not import hidden `pyparsing._noncomma`, instead reconstruct it

because `_noncomma` has been removed in `pyparsing >= 2.0.1`.
This change makes `pydot >= 1.1.0` compatible with `pyparsing >= 1.5.7`.

pydot/pydot,erocarrera/pydot