• Update corebird to 1.3 release
• Remove unneeded patches
• Drop libgee dependency
• Add USES=compiler:c++11-lang

Changelog:

https://github.com/baedert/corebird/releases/tag/1.3

Reviewed by: feld, junovitch (mentors)
Approved by: feld, junovitch (mentors)
Differential Revision: D7392