maint: prepare for next release number

maint: prepare for next release number

Given Daniel's announcement[1], code targetting the next release will
be in 1.0.0, not 0.10.3.  Changed mechanically with:

for f in $(git grep -l '0\(.\)10\13\b') ; do
   sed -i -e 's/0\(.\)10\13/1\10\10/g' $f
done

[1]https://www.redhat.com/archives/libvir-list/2012-October/msg00403.html

* docs/formatdomain.html.in: Use 1.0.0 for next release.
* src/interface/interface_backend_udev.c: Likewise.