Introduced a version controlled sqlite3 database

KeyvalueDb adapter simply handles connection, disconnection and automatic schema upgrades.

It is not meant for heavy duty, one-size-fits-all adaptation - the objective is speed. Even if it means having to use switches all over the place.

It can be theoretically adapted to support multiple database types but at present the support would have to be baked straight in to KeyvalueDb and the API.

New API method 'export' added to export keys - presently, CSV format only.