Initial implementation for Comments - not working

Still can't get the Comments to show up in the generated Ruby output.
Committing so I can look at a different branch of code to see if my
previous work is still there.
Fixed comments (model and mtl)

Code in mtl had to be moved to correct position. The model had to have
its .uml modified so the comments were correctly owned by the Class and
not the Model.
Unit tests for Comments

Added a unit test that compares the expected with autogen ruby code
Added line to run_all_test.sh
Merge pull request #43 from uiuc-cs428/Iteration3_Comments2

Iteration3 comments2