Merge branch 'maint'

Merge branch 'maint'

* maint:
  docs: fixlet about xz compression levels and command line options
  maint: more files excluded in 'update-copyright'
  maint: adapt 'update-copyright' recipe to the new $(FETCHFILES) format
  HACKING: update instructions to update the manuals at www.gnu.org
  maint: add an explicative comment in Makefile
  maint: factor out the name of the dir where web manuals are generated
  maint: rename rules to build/upload web manuals
  cosmetic: minor variable and rules reordering in Makefile.am
  docs: build the web manuals for CVS in the builddir, not in the srcdir
  release: automate uploading of web manuals in CVS
  docs: AM_CFLAGS: remove reference to non-existing "more detailed" desc
  tests: avoid two spurious failures on FreeBSD
  tests: improve 'pkg-config' requirement