fixed pause/resume. goes with fixes in core.
Merge pull request #38 from gameclosure/fix-pause-resume

fixed pause/resume. goes with fixes in core.
updated core submodule ref
added device orientation change event: unknown; portrait, portraitUpsideDown; landscapeLeft, landscapeRight. removed unused imports.
Merge pull request #39 from gameclosure/feature-allow-rotation

added device orientation change event: unknown; portrait, portraitUpside...  LGTM @chris-gc