Versioning scheme changes.

HPA suggests it is simply silly to imitate Linux versioning
scheme where the leading "2" does not mean anything anymore, and
I tend to agree.

The first feature release after 1.0.0 will be 1.1.0, and the
development path leading to 1.1.0 will carry 1.0.GIT as the
version number from now on.  Similarly, the third maintenance
release that follows 1.0.0 will not be 1.0.0c as planned, but
will be called 1.0.3.  The "maint" branch will merge in fixes
and immediately tagged, so there is no need for 1.0.2.GIT that
is in between 1.0.2 (aka 1.0.0b) and 1.0.3.

Signed-off-by: Junio C Hamano <junkio@cox.net>