update an existing counter rather than overwrite it.
This turns out to be more complicated than it might seem. There are two
large parts to the patch. One moves the counter read routine out of TextClass
and into the Counter and Counters classes. The other changes the syntax of
counters from:
Counter
Name whatever
....
to:
Counter whatever
....
This allows us to get the name of the counter right away, so we can decide
whether it is an old one or a new one. So the layout format had to be
changed (again), with corresponding layout2layout code.
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@26779 a592a061-630c-0410-9148-cb99ea01b6c8
d841355b7e