#12 Pruning startis in a wrong directory

[Pavel Roskin]

I expect "cvsgrub -prune" to prune the directories it
has updated, i.e. the ones under the current directory.
That's what CVSGrab::getPackagePath() returns.
_localProjectDir makes no sense and usually points to a
non-existing directory. The patch removes all
references to _localProjectDir.