Add tests for removal of left-unary ? operator (and the fixed JOIN because of it).
Add tests for removal of left-unary ? operator (and the fixed JOIN because of it).

lfittl/pg_query,cmrtn/pg_query,lfittl/pg_query,jcsjcs/pg_query,sshao/pg_query,JackDanger/pg_query,jcsjcs/pg_query,jcsjcs/pg_query,purcell/pg_query,JackDanger/pg_query,cmrtn/pg_query,purcell/pg_query,sshao/pg_query