Merge branch 'jk/cvsimport-does-not-work-with-cvsps3'

Warn people that other tools are more recommendable over cvsimport+cvsps2 combo when doing a one-shot import, and cvsimport will not work with cvsps3. * jk/cvsimport-does-not-work-with-cvsps3: git-cvsimport.txt: cvsps-2 is deprecated