Mir Display Server Lands API Changes, Relicenses Headers To LGPL

Canonical's Mir developers are working to get Mir 1.0 released in 2017 and in preparation for that stable milestone they have just landed a number of API changes.

Just a few days ago we were talking about the Mir 0.26 features while the latest Mir happenings is a number of API changes. Today there were a number of new APIs published for the Mir client library, the Mir render surface APIs were deprecated, and other API changes.

Besides all the API changes, a fundamental change is that all the Mir headers have changed from being GPL to now under the LGPL.

More details on the interface changes via this Bzr commit. That's also been followed up with other API additions and deprecations.