Add field to support "WITH TIME ZONE".

Add parsing for UNION and outer JOINs.
Implement SQL92 "WITH TIME ZONE".
Allow some reserved words as identifiers and column labels.
Clean up indentation and "orphan spaces and tabs".

Generate non-fatal warning only and proceed by ignoring clauses.

Include reserved words for string handling, outer joins, and unions.

Implement extended comments ("/* ... */") using exclusive states.
Modify definitions of operators to remove some restrictions on characters
 and character order.

   Fix very old bug which made tuples changed/inserted by a commnd
visible to command itself (so we had multiple update of updated tuples,
etc).

visible to command itself (so we had multiple update of updated tuples,
etc).