a RowProxy result row such that no exception
throw is generated internally;
NoSuchColumnError() also will generate its
message regardless of whether or not the column
construct can be coerced to a string.
[ticket:2178].

dialect for 0.6, courtesy Florian Apolloner.
[ticket:1906]

which has not yet been assigned a name, i.e. as in
declarative, is used in a context where it is
exported to the columns collection of an enclosing
select() construct, or if any construct involving
that column is compiled before its name is
assigned.  [ticket:1862]

allowed cursor errors to be raised consistently broke
the result.lastrowid accessor.   Test coverage has
been added for result.lastrowid.   Note that lastrowid
is only supported by Pysqlite and some MySQL drivers,
so isn't super-useful in the general case.

- improved pool docs
- typos etc.
- ClauseElement.execute() and scalar() make no sense - these are depreacted.
The official home is Executable.
- alias() is not executable, allowing it is sloppy so this goes under
the deprecated umbrella

has already been exhausted, has been closed,
or is not a result-returning result now
raises ResourceClosedError, a subclass of
InvalidRequestError, in all cases, regardless
of backend.  Previously, some DBAPIs would
raise ProgrammingError (i.e. pysqlite), others
would return None leading to downstream breakages
(i.e. MySQL-python).

- Connection, ResultProxy, as well as Session use
ResourceClosedError for all "this
connection/transaction/result is closed" types of
errors.