Silence debugging output from ptiff
Clean style and Pythonify code of PtiffTileStore
Fix a bug where ptiff views were not being removed from sessions
Fix inappropriate log levels in PtiffTileStore
Fix misspelling of "Philips"
Merge branch 'ptiff_clean'

* ptiff_clean:
  Fix misspelling of "Philips"
  Fix inappropriate log levels in PtiffTileStore
  Fix a bug where ptiff views were not being removed from sessions
  Clean style and Pythonify code of PtiffTileStore
  Silence debugging output from ptiff
Fully refactor Database models to ImageStore

The view code still uses the old class names, but these are exported
for compatability during the transition.
Make to_pymongo return a raw object only optionally

This allows the MongoProxy wrapper, which handles AutoReconnect exceptions,
to be used anywhere except in a GridFS.
Merge branch 'database_imagestore'

* database_imagestore:
  Make to_pymongo return a raw object only optionally
  Fully refactor Database models to ImageStore