The common package defines the interfaces that a protocol must implement
and contain code that can be shared among supported protocols.
This way should be easier to support new protocols
added the "initprovider" command to initialize the database structure.
If we change the database schema the required changes will be checked
at startup and automatically applyed.
The `memory` provider can load users from a dump obtained using the
`dumpdata` REST API. This dump file can be configured using the
dataprovider `name` configuration key. It will be loaded at startup
and can be reloaded on demand using a `SIGHUP` on Unix based systems
and a `paramchange` request to the running service on Windows.
Fixes#66
an user can now be disabled or expired.
If you are using an SQL database as dataprovider please remember to
execute the sql update script inside "sql" folder.
Fixes#57