Merge branch 'many-minor-fixes' into 'master'

dune/gfe/assemblers/cosseratrodenergy.hh

dune/gfe/assemblers/localgeodesicfeadolcstiffness.hh

dune/gfe/assemblers/localintegralenergy.hh

dune/gfe/densities/bulkcosseratdensity.hh

dune/gfe/densities/chiralskyrmiondensity.hh

dune/gfe/densities/localdensity.hh

dune/gfe/localgeodesicfefunction.hh

dune/gfe/localprojectedfefunction.hh

dune/gfe/spaces/unitvector.hh

src/cosserat-continuum.cc

src/film-on-substrate.cc

src/gradient-flow.cc

src/harmonicmaps.cc

src/rod3d.cc

src/simofoxshell.cc

test/cosseratcontinuumtest.cc

test/cosseratrodtest.cc

test/filmonsubstratetest.cc

test/geodesicfeassemblerwrappertest.cc

test/harmonicmaptest.cc