Add `Select.get_final_froms()` (sqlalchemy#217)

https://docs.sqlalchemy.org/en/14/core/selectable.html#sqlalchemy.sql.expression.Select.get_final_froms

Fix `Connection.connection` to return `_ConnectionFairy` as documented (

sqlalchemy#216)

https://docs.sqlalchemy.org/en/14/core/connections.html#sqlalchemy.engine.Connection.connection

212-Add typings (sqlalchemy#213)

* 212-Add typings

* 212-Add typings for classes

* Minor refactoring

* run zimports

Co-authored-by: Federico Caselli <[email protected]>

fix(sql.schema): alias typing.Sequence -> _Sequence to avoid conflict…

… with class Sequence (sqlalchemy#210)

Fixes: sqlalchemy#209

fix: add execution_options to session.get (sqlalchemy#205)

* fix: add execution_options to session.get

Fixes: sqlalchemy#204

* fix: add execution_options to get in ext/asyncio

Add `nesting` flag in CTE functions (sqlalchemy#188)

reorder inspect targets (sqlalchemy#182)

it looks like at least in pylance the order
of overloads is important, from more specific to more
general, so reorder these.

Co-authored-by: Federico Caselli <[email protected]>

don't use typing with ServerDefaultType (sqlalchemy#180)

The server default is any expression that is passed as DDL
to the database and these usually don't have SQL types explicitly
stated.

With the code as is, pylance is complaining about this:

    Column(DateTime(), server_default=func.now())

and requiring I do this:

    Column(DateTime(), server_default=func.now(type_=DateTime))

people don't need to do that, server_defaults SQL type always comes
from the column type and doesn't normally need to be stated.

Also, column_server_default.py was importing "functions as func",
which is wrong. "func" is not a module it's a namespace object,
fixed that.

fix formatting and typo

Common execute params (sqlalchemy#168)

* Add a single definition for all execution parameters

* Use a single definition for execution options