Revision 429491

- Add mirror for distfile
- Use standard CC-BY-NC-SA-3.0 license
- Add gl to USE_GL
- Remove bsd.port.options.mk include
- Use new options helpers
- Use EXTRACT_* variables for post-extract target
- Use POST_PLIST for build-plist-empty target

PR:		215539
Submitted by:	lightside@gmx.com (maintainer)