Updated ParseProducts.

- ParseProducts are not associated with Dependencies anymore, they store
	their Dependency info in a list of dicts since there's info in the
	pipeline that can't be stored just in a Dependency object.
- ParseProducts now inherit from NonPrimaryKeyEquivalenceMixin.
Removed more debug code
StringProcessor unit tests now passing.

- StringProcessor no longer deals with Dependency objects since storing
  info is complicated and gets into related objects and such.
- Fixes #49.
Removed unnecessary dependencies.