Merge pull request #4218 from RosettaCommons/roccomoretti/interactive_split_rosetta_util
Foldit: Separate out dependencies on Rosetta in lower-levels of interactive/
It looks like most of the lower-level GUI code is only trivially dependent on Rosetta proper. Attempt to separate this out cleanly, to ease a future frontend/backend split.
The big task here was splitting interactive/util in two, removing the Rosetta-depedendent functionality into interactive/rosetta_util. Once accomplished, with a few minor adjustments all the gui code below interactive/poseview is now independent of the main Rosetta codebase. The levels script (and associated documentation) was updated accordingly.