* configure.in: more sanity checking for the gtkxmhtml test. Also
changed datadir to include the gimp version too. So right now
only the development headers conflict between versions in the same
prefix.

* gimptool.in
* gimptool.1: added and documented configure variable query options
(bindir, sbindir, sysconfdir, etc.)

* tips/Makefile.am: add gimp_tips.uk.txt

-Yosh