Ensure monkey patched code is reflected in Opal

[wied03]

See through Opal PRs for monkey patched code:

• - Pathname#entries - Resolves #1407, Implement Pathname.entries (Node.js) opal/opal#1408
• - Dir.glob multiple list fix - rubyspecs for glob need FileUtils, see discussion on Resolves #1407, Implement Pathname.entries (Node.js) opal/opal#1408
• - Pathname#relative_path_from, File::FNM_SYSCASE - Implement Pathname#relative_path_from opal/opal#1445

[wied03]

work from #12