Start 0.9 series
Start 0.9 series

Decouple ABI/API versioning from the package version number, there is no
reason for having a broken ABI/API every time we change librest minor
version number.
For now, API version stays at 0.7 as API/ABI hasn't been broken yet. If
we were to break it, we can go directly up to 1.0 and attempt to stick
to a stable API. ABI can still be broken through soname changes (but
it's also better if we can avoid it).

GNOME/librest,GNOME/librest,GNOME/librest