fix: refactor code so most things work without sqlalchemy

also refactor tests to help ensure that remains true

Add wutta wrapper for `short_session()`

and several related tweaks for tests, docs

Move tests out of the installed package set

this seems to be better practice. from what i can tell this is a
clean move with no breakage.. and built package files no longer seem
to include test modules

Make 'tests' a proper subpackage again; add some tests

Trying to make more of an effort here...

Add `User.get_email_address()` and `User.email_address`.

For now, these will do. Probably need to revisit that at some point.

Rework how Continuum versioning is configured.

The burden for configuring this now falls to the application entry point,
although that may not be a bad thing. Even then, versioning is *not*
enabled by default so config must explicitly enable it.

General header / Unicode cleanup.

This hopefully updates all module headers such that the file encoding is
utf-8, and uses Unicode literals, etc.

Database config/init overhaul.

This contains some not-very-atomic changes:

* Get rid of `get_session_class()` function and return to global `Session`
class approach.
* Primary database `Session` is now configured as part of command
initialization, by default.
* Make `config` object available to subcommands, and `Daemon` instances
(the beginning of the end for `edbob.config`!).
* Add `--stdout` and `--stderr` arguments to primary `Command`. These are
in turn made available to subcommands.
* Overhauled some subcommand logic per new patterns.
* Get rid of a few other random references to `edbob`.
* Added and improved several tests.
* Added ability to run tests using arbitrary database engine.