fix for Ambiguity.equals
Adding hashCode implementation for Ambiguity and fixing one of the junit tests.
Merge pull request #681 from kframework/fix-for-ambiguity-equals

Fix for ambiguity equals
Fixing set membership
Added test for set membership
Checkstyle problems
Checkstyle again
Merge pull request #687 from kframework/fixing-set-membership

Fixing set membership
Updated definitions in 5_typed
added all tests in 5_types
Merge branch '5_types-updated' of github.com:grosu/k into 5_types-updated