pep8 updates (triple single quotes to double single quotes)
better doc string
restructure since future preference classes will form the base or preference lookups
Removing "default" folder since it introductes needless complexity.  In addition if there is ever a version called "default" it will cause problems if specilized preference files are required
Removing "default" folder since it introductes needless complexity.  In addition if there is ever a version called "default" it will cause problems if specilized preference files are required
adding filename keyword so subclasses to 'prefix' their queries
added check for notset and ensuring the key does not start with the filename
better comment callout
import fix
initial work on database url construction