[git][readme] Initialize the repository readme.md with basic information

CMakeLists.txt

@@ -24,6 +24,7 @@ dune_enable_all_packages()
 
 add_subdirectory(doc)
 add_subdirectory(cmake/modules)
+add_subdirectory(appl)
 
 # finalize the dune project, e.g. generating config.h etc.
 finalize_dune_project(GENERATE_CONFIG_H_CMAKE)

README.md

+## SFB-1313 Summer School 2021: Porescale evaluation of REV Scale Coupling Conditions
+
+This repository will house all of the dumux based simulations used during the
+2021 SFB1313 Summer School. Simulations are found within the `appl` or applications
+folder.
+
+You can configure the module just like any other DUNE module
+by using `dunecontrol`. For building and running the executables,
+please go to the build folders corresponding to the simulation sources listed above.
+

appl/CMakeLists.txt

+add_subdirectory(porescale)
+add_subdirectory(coupled)