setup-db: perform an initial repository scan as stated by the docs (Issue #302) The documentation, as well as the prompt text inside setup-db itself, states that the repository root location will be scanned automatically for existing repositories. However, this is not actually the case. Only exception is when the 'initial_repo_scan' is set to True in the ini file; in that case the scan is done on each start of Kallithea. Add the required repo scan logic at the end of setup-db, after setting up the application completely (the database has only just been set up). The app setup code from BasePasterCommand is duplicated - this command doesn't fit in and need to run both before and after database creation. The scan call from kallithea/config/app_cfg.py is also duplicated - that will be removed next.