File Classification Fix

Fixed an issue with how models were being classified by extension.
Cleaned up Annotator.java and redid how buttons are sorted in
preparation for adding additional sorting methods
Cleaned up the code. Removed commented out or unused/dead sections of
the code.
Added new sort codeword by annotation completeness feature to the
Annotator.
Commented out code which loads SBML.dll for now.
Revert "Added new sort codeword by annotation completeness feature to the"

This reverts commit 15c2f0a5ed93f88cc49c6a5d8f1c827e6de1ad43.
Revert "Revert "Added new sort codeword by annotation completeness feature to the""

This reverts commit c393cc4a8c9ac5b264961621b0bd105d8dcad670.
Renamed some of the objects in new sort function to make their purpose
clearer.
Changed return type for composite completeness in codeword buttons to
enum.
Additional code cleanup.
Uncommented the SBML dll file check.
Merge pull request #1 from thompsct/Usability-Improvements

Usability improvements - Added new annotation sort option along with general code cleanup.