Cleaned up implementation

Also fixed bug where unexpected result appeared when having a model with
unSAT errors that contained comments.
Merge branch 'develop' into i59
new version
Cleaned up unSAT implementation
Fixed a bug relating to i31
Fixed issues relating to the previous commit
Fixed bug resulting from fixing i74

http://gsd.uwaterloo.ca:8888/question/338/problem-with-translation-of-abstract-clafers-in
Changed implementation of findNeccecaryBitwidth so that takes advantage of the IR
Fixed bug where getId function looked up wrong Id
updated package versions, new version, cabal >= 1.16, test cases for i74
Changed how IG responds to scope increases beyond bitwidth capcity

IG now simply reports the too large scope and increase the bitwidth to
allow it
Fixed a bug where for certain models calling AlloyModel cause a fromJust error
Added emptyFile check to give a better error message
Edited error message from previous commit
Edited the IG test infrastructure to match that of Clafer's
Fixed a bug where sometimes UnSAT was not shown when calling claferModel in certain cases

Also Moved backquoted as it has yet to be fixed
Change the implementation of the previous bug fix

Slightly less error prone than the last fix
Rearranged test files
Merge pull request #10 from gsdlab/i59

Cleaned up implementation