Merge pull request #130 from trontrytel/master

changes in plots for paper and fix for iga in the divergent flow correction
better colour scale in boussinesq test
Merge pull request #133 from slayoo/master

better colour scale in boussinesq test
wip on test nug
Merge github.com:igfuw/libmpdataxx
fix in dfl 2d option + final setup for bcbf test (dfl option does not help)