Following the project member list cleanup, only backends that list
a project member with git write access in the AUTHORS file are now
considered maintained.
* configure, configure.in: version 1.0.21cvs
* doc/releases.txt: minor updates for new build system
* doc/descriptions/canon_dr.desc, doc/descriptions/coolscan3.desc,
doc/descriptions/rts8891.desc, doc/descriptions/xerox_mfp.desc:
remove :new tag