the indexing.  this is for more natural operation.
- also add cast() to the JSON expression to complement astext. This integrates
the CAST call which will be needed frequently.  Part of [ticket:2687].
- it's a little unclear how more advanced unicode attribute-access is going to go,
some quick attempts at testing yielded strange error messages from psycopg2.
- do other cross linking as mentioned in [ticket:2687].

:class:`.Column` is mapped multiple times under different properties
(which typically should be a :func:`.synonym` instead) or if two
or more :class:`.Column` objects are given the same name, raising
a warning if this condition is detected. [ticket:2828]

to query from the ``rdb$relations`` view instead of the
``rdb$relation_fields`` and ``rdb$view_relations`` views.
Variants of both the old and new queries are mentioned on many
FAQ and blogs, however the new queries are taken straight from
the "Firebird FAQ" which appears to be the most official source
of info. [ticket:2898]

underscore.  Courtesy Treeve Jelbert. [ticket:2897]

of each can be reflected independently.  Testing [ticket:2898] at the moment.

index were not sorted correctly; they are now sorted
in order of RDB$FIELD_POSITION.

work with Firebird dialects; previously the decimal conversion was
not occurring.
- scale back some firebird FP numeric tests

Remove terminated connections from the pool.