adg-demo: added custom error handling
adg-demo: reordered main operations
adg-demo: added command line parsing
adg-demo: added title block handling
adg-demo: parametrized chamfer value
adg-demo: added left and right click handling
adg-demo: added optional groove machining

Now adg-demo.lua is in par with adg-demo.c.
doc: updated README
doc: updated THANKS
adg-demo: corrected first title block update

Updating the title block after having generated it the first time. Avoid
setting the metadata because they will be overwritten anyway.
doc: updated NEWS
build: removed adg-demo.lua from dist

The Lua script is generated by configure from adg-demo.lua.in, yet in
dist: no need to include a duplicate of it.
build: raised adg dependency on 0.7.2

adg-lua is actually developed together with adg: no need to keep old
stuff around.
build: bumped version to 0.1.1