[parted-devel] sync with gnulib, etc.

[Jim Meyering]

Thanks to Joel Granados for noticing that 1.10b wasn't adequate.
I've adjusted dependencies both in bootstrap.conf and in configure.ac.
I noticed that we were using an old, vc'd-in-parted version of
vc-list-files (used as part of "make syntax-check"), that is now
incompatible.  I've removed it and changed bootstrap.conf so the
latest is always pulled from gnulib.

Also, Joel noticed that there was still a bogus gnulib_dir
definition in cfg.mk.  I removed it, now that I've tweaked
gnulib's maint.mk to do the right thing by default.