Introduce `%SUB-MAIN-OPTS<numeric-suffix-as-value>` (#5025)
Introduce `%SUB-MAIN-OPTS<numeric-suffix-as-value>` (#5025)

* Introduce SUB-MAIN-OPTS<numeric-suffix-as-value>

This allows CLI arguments of the form -j2 to be interpreted as
--j=2, making it more compatible with "normal" CLI argument interpreters

* Only do conversion for single letter args

* Allow only numeric suffixes, not anything else after that

* Make numeric suffix check less CPU intensive
tbrowder/rakudo,MasterDuke17/rakudo,salortiz/rakudo,tbrowder/rakudo,rakudo/rakudo,MasterDuke17/rakudo,rakudo/rakudo,salortiz/rakudo,tbrowder/rakudo,rakudo/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,salortiz/rakudo,rakudo/rakudo,tbrowder/rakudo,MasterDuke17/rakudo,salortiz/rakudo,rakudo/rakudo,salortiz/rakudo,tbrowder/rakudo,tbrowder/rakudo,rakudo/rakudo,salortiz/rakudo,MasterDuke17/rakudo