- [feature] Added "MATCH" clause to ForeignKey,

- [feature] Added "MATCH" clause to ForeignKey,
ForeignKeyConstraint, courtesy Ryan Kelly.
[ticket:2502]
- [feature] Added support for DELETE and UPDATE from
an alias of a table, which would assumedly
be related to itself elsewhere in the query,
courtesy Ryan Kelly.  [ticket:2507]
- [feature] Added support for the Postgresql ONLY
keyword, which can appear corresponding to a
table in a SELECT, UPDATE, or DELETE statement.
The phrase is established using with_hint().
Courtesy Ryan Kelly [ticket:2506]