Sterne beta

This includes some minor performance fixes principally focused on Bookworms of over 1 million documents, and some bugfixes. All other branches have been deleted, so we can now focus solely on developing master for the time being.

It's only been tested on smaller productions (indeed, a full test suite is a real need); I would love to head any errors.

New features

• Some additional date rounding features; rounding is still not fully documented, but the general terms are available from the code in parseMetadata.py

Performance Improvements

• Booklists are now saved using the anydb python module on disk, which saves a lot of memory in the encoding step for large bookworms.
• The settings to parallel have been tweaked to run slightly faster.
• Catalog parsing now takes place in parallel as well; with sets over 1 million volumes, this can be a significant improvement.

Bugfixes

• Variables with the same name as a reserved MySQL word will now be dropped.

Usability improvements

• Fewer branches.
• Less extraneous output written to stdout during a build.
• Warning messages more consistently sent to stderr rather than stdout.