Added tag release-2.7.2 for changeset 6a449b8e3c88
update docs for release 2.7.2
doc/Makefile: adapt to Qt6 qhelpgenerator
NEWS: announce UNO improvements
NEWS, DESCRIPTION: prepare for release 2.7.2
NEWS, DESCRIPTION: prepare for 2.7.2 release.
Require Java >= 1.9 for Octave 11+ (bug #68350)
csvconcat.cc, csvexplode.cc: code updates.