[Dune] Modularisierung

[Christian Engwer]

Hi there :-)

I slightly improved the dunecontrol script.

You can now write an opts file (see dune-common/bin/example.opts) and
supply this to dunecontrol

./dune-common/bin/dunecontrol --opts=foo.opts all

This opts file does contain default parameters for the different
commands. When calling something like

./dune-common/bin/dunecontrol --opts=foo.opts make clean

dunecontrol will ignore the opts file (because you supplied command
parameters on the command line) and warn you...

WARNING: commandline parameters will overwrite setting in opts file "/path-to-optsfile/foo.opts"

Bye Christian