Cnx-db

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- Remove the ``DB_NAME`` environment variable from the container definition.
This appears to have become redundant with the ``POSTGRES_DB`` variable.
- Fix .dockerfiles/initdb.d/00_initdb.sh to look for ``*.sql``
and ``*.sql.gz`` files in the docker entrypoint directory rather than
the current working directory.

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- Simplify slim dump import into docker container

- Rename .dockerfiles/initdb.d/initdb.sh to 00_initdb.sh
- Don't run cnx-db init if ``*.sql`` or ``*.sql.gz`` exist
- Remove .dockerfiles/initdb.d/load_database_dump.sh
- Set POSTGRES_DB to the same as DB_NAME

- Add the baked and print-style columns to the module metadata query.

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- Massage testing fixtures to better facilitate testing in packages using
this package.

- Provide additional init and wipe fixtures scoped at the module level.
- Remove custom function for table name lookup. Replaced by sqlalchemy
Inspector methods.
- Add a ``db_tables`` pytest fixture that supplies sqlalchemy table objects.

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- Add a new baking state, known as 'fallback', that allows content
to remain in a success state even when the latest print-style
won't work with the content.
- Fix the primary key on the ``print_style_recipes`` table.
- Provide docs for using the Pyramid Web Framework with this package.
- Add a database tables definition to the pyramid integration.
This places a ``tables`` attribute on the registry.
The attribute contains sqlalchemy table definitions that are reflected
from the existing database schema.

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- Fix settings discovery to use the given settings value for 'db.common.url'
when the ``DB_URL`` environment variable is undefined.
- Add a read-only database setting to allow for read-only database
connections. The setting is available through the ``DB_READONLY_URL``
environment variable.

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- Touchup the docstrings for database init funcs (99)
- Add an integration point for the pyramid web framework (98)
- Update documentation headers and contrib module api docs (97)