Formatting
Database overhaul.
Continuing overhaul. Adding a persistent connection and cursor as data member of Catalog. This should speed things up as well as avoiding two different connections working on the same commit (in this case, I was commiting in the parent or sharing the cursor explicitly). addRelease(), deleteRelease()  and report() tested OK.
Move this import into these infrequently-used functions.
Grouping this function with similar ones.
Expanding comment
These functions now need to commit their changes.
Updating coverart code. Was fetching the whole release dict.