Change to return the exception object when an exception occurred in mrb_funcall
Add test cases.
Add "Comparable" to labels.
Add comments: eval method is defined in mrbgems.
Add comments: some methods is defined in mrbgems.
Adjust ci->nregs to prevent heap corruption
Merge pull request #1128 from monaka/pr-add-iso-confomance-tests-20130402

Add ISO confomance tests
Merge pull request #1130 from gzohari/adjust_ci_nregs

Adjust ci->nregs to prevent heap corruption
Merge pull request #1131 from takkaw/mrb_funcall_return_exc

Change to return the exception object when an exception occurred in mrb_funcall