Implement TIFF input data.

.ci/README.md

.ci/setup.sh

.travis.yml

CMakeLists.txt

README.md

appveyor.yml

cmake/modules/DuneCopasiMacros.cmake

docker/dune-copasi.dockerfile

dune/copasi/local_operator.hh

dune/copasi/local_operator_multidomain.hh

dune/copasi/model_multidomain_diffusion_reaction.cc

dune/copasi/muparser_data_handler.hh

dune/copasi/pdelab_expression_adapter.hh

dune/copasi/tiff_grayscale.hh

lib/CMakeLists.txt

src/CMakeLists.txt

test/CMakeLists.txt

test/data/tiff/flower-minisblack-04.tif

test/data/tiff/flower-minisblack-08.tif

test/data/tiff/flower-minisblack-16.tif