Fixed parsing of expressions with right-associative infixed operators.  In ML90 an expression with different operators with the same precedence treated them as left-associative even if they were both declared as right-associative.  In ML97 different operators of the same precedence must both be left-associative or both right-associative but different right-infixed operators should work as expected.  The code added to handle this in ML97 was wrong and in the recent clear-out of ML90 compatibility it no longer worked even with multiple occurrences of the same operator.  This fixes these bugs.
Fixed parsing of expressions with right-associative infixed operators.  In ML90 an expression with different operators with the same precedence treated them as left-associative even if they were both declared as right-associative.  In ML97 different operators of the same precedence must both be left-associative or both right-associative but different right-infixed operators should work as expected.  The code added to handle this in ML97 was wrong and in the recent clear-out of ML90 compatibility it no longer worked even with multiple occurrences of the same operator.  This fixes these bugs.

git-svn-id: 98787b36aaefbae4b30fa755be920954cd25e1e4@639 ae7d391e-3f74-4a2b-a0db-a8776840fd2a

mn200/polyml,dcjm/polyml,mn200/polyml,polyml/polyml,polyml/polyml,polyml/polyml,mn200/polyml,dcjm/polyml,dcjm/polyml,mn200/polyml,polyml/polyml,dcjm/polyml