Remaining things to merge before 2016.02-rc1:
- Bump of ARC toolchain to 2015.12, so that when the external Buildroot toolchains will be rebuilt, we'll use the newer ARC tools
- The atomic series, since it fixes a number of build failures, and will allow to fix more of them
- Gtk2/Gtk3 circular dependency fixes from Yann.
Needed for 2016.02, but can wait after -rc1:
- The patch series clarifying the licensing of the patches
- As many musl build fixes as possible