trivial: Add a 'make clang' target
Always return an error if cd_main_device_add() failed
trivial: Fix up a clang false-positive that can't happen in reality
trivial: Use g_error_matches() to avoid another clang warning
trivial: NULL != FALSE for some compilers
Add some missing G_BEGIN_DECLS/G_END_DECLS in header files

This ensures libcolord can be used in C++ applications.
trivial: Add a C++ example
trivial: Remove trailing comma from enum

Some compilers barf at this.
trivial: Include a couple of missing config.h includes
trivial: Add a FAQ entry about the new version numbers
Use G_GNUC_WARN_UNUSED_RESULT in public and private headers
trivial: Post branch version bump