- Use Github as the source.
- Depend on devel/py-gyp and japanese/zinnia because bundled versions have
  been removed from the original distfile.
- devel/py-gyp-devel has been updated to snapshot as of 20160504 and
  renamed with devel/py-gyp.  Take maintainership[*].
- Install mozc.el.gz instead of mozc.el.

Approved by:	maintainer [*]