build tetrahedron refinement rules into library

The TET_RULESET compile-time option could be used to load tetrahedron refinement rules from RefRules.data, however this requires to locate the file at run-time. This was too inconvenient.

Instead generate RefRules.cc from RefRules.data including the refinement rules and use that.

gm/CMakeLists.txt

 set(SOURCES  algebra.cc enrol.cc evm.cc mgio.cc
   ugio.cc ugm.cc cw.cc initgm.cc elements.cc
   shapes.cc evalproc.cc rm.cc refine.cc
-  dlmgr.cc gmcheck.cc er.cc mgheapmgr.cc)
+  dlmgr.cc gmcheck.cc er.cc mgheapmgr.cc rm-write2file.cc )
 # put this "template" into distribution-tarball as well
 set(EXTRA_DIST  dlmgr.t)
 set(gminclude_HEADERS  cw.h elements.h gm.h pargm.h evm.h
-  shapes.h ugm.h dlmgr.h algebra.h rm.h refine.h)
+  shapes.h ugm.h dlmgr.h algebra.h rm.h refine.h rm-write2file.h)
 
 ug_add_dim_libs(ug_gm OBJECT SOURCES ${SOURCES})# OBJECT_DIM_LIBS gg)
 
+dune_add_test(
+  NAME rm3-tetrahedron-rules-test
+  SOURCES rm-tetrahedron-rules-test.cc
+  COMPILE_DEFINITIONS -DUG_DIM_3
+  LINK_LIBRARIES ugL ugS3 ${DUNE_LIBS}
+  CMAKE_GUARD DUNE_UGGRID_TET_RULESET
+  )
+
+# rm3-show
+add_executable(rm3-show rm-show.cc)
+target_compile_definitions(rm3-show PRIVATE -DUG_DIM_3)
+target_link_libraries(rm3-show PRIVATE ugL ugS3 ${DUNE_LIBS})
+
+# rm3-writeRefRules2file
+add_executable(rm3-writeRefRules2file rm-writeRefRules2file.cc rm-write2file.h rm-write2file.cc)
+target_compile_definitions(rm3-writeRefRules2file PRIVATE -DUG_DIM_3)
+target_link_libraries(rm3-writeRefRules2file PRIVATE ugL ugS3 ${DUNE_LIBS})
+
 install(FILES ${gminclude_HEADERS} DESTINATION ${CMAKE_INSTALL_PKGINCLUDEDIR})