added comments and examples to IR datatypes
Merge pull request #21 from gsdlab/i92

Fix for issue i92 with refrences to clafers (not addressing the parsing issue with integers)
Improved performance.
Fixed parentof, refto, colonto.
Fixed i235, in this situation treat '->' as ':'
stop copying the executable to root dir. new version after merging pull reg i92
Fixed i235 for ss=simple, ignore prev commit

http://gsd.uwaterloo.ca:8888/question/976/error-in-alloy-generator-maybefromjust-nothing
Fixed merge issues
Merge branch 'develop' into i236
Merge pull request #22 from gsdlab/i236

I236
fixed merge conflict from develop
Merge pull request #24 from gsdlab/i235

I235
Merge branch 'develop' into i74
test case from i74