Bug #19642 for Jifty: Schema creation with missing libraries

I was attemping to set up database tables for BTDT (BestPractical's internal application) using C<jifty schema --setup>, without all the required modules installed. The schema setup process proceeded, but reported errors on missing modules, as well as the inability to refer_to model classes that had not loaded properly, apparently leaving the database schema in an inconsistent state. Upon installing the required dependencies and re-running C<jifty schema --setup>, Jifty reported that the database was up-to-date, and allowed the application to start with C<jifty server>. However, the application proceeded to throw errors on inserts into the database, since some of the tables did not exist. Correct behavior is probably for C<jifty schema --setup> to error earlier in the process and fail under these circumstances, rather than leaving the database in an inconsistent state, but with metadata indicating it's been set up appropriately. - Nelson Elhage