[PGE]: pgc.pir - added "is optable" trait for rules, to allow a grammar to designate entry rules into the (default) operator precedence table.
[PGE]: pgc.pir - added "is optable" trait for rules, to allow a grammar
to designate entry rules into the (default) operator precedence table.


git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@13075 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot