Support extension '.cc' in globbing.
Correct comment in exception test.
Merge pull request #2299 from take-cheeze/cc_ext

Support extension '.cc' in source code listing.
Merge pull request #2300 from yui-knk/fix-comment

Correct comment in exception test.
break in blocks cannot cross C function boundaries; fix #2298
direct invocation of module_eval; ref #2298
Check mrbc_context is null
direct invocation of instance_eval
Merge pull request #2301 from mimaki/fix-load-mrb-segv

mrb_load_irep_file() caused SEGV