Add cmake option WALBERLA_LOG_SKIPPED

This option is OFF by default.
If turned on cmake will notify if a target cannot be build due to a missing module.
35 jobs for mute-cmake-target-skipp in 460 minutes and 8 seconds (queued for 46 seconds)
Status Job ID Name Coverage
  Pretest
passed #282234
docker
clang_8.0_hybrid_dbg_sp

00:36:34

passed #282233
docker
gcc_9_hybrid

00:14:53

 
  Test
passed #282256
docker
clang-tidy

00:04:13

passed #282250
docker
clang_4.0_hybrid_dbg

00:22:46

passed #282251
docker
clang_8.0_hybrid

00:16:39

passed #282254
docker
clang_8.0_hybrid_dbg

00:14:37

passed #282253
docker
clang_8.0_mpionly_dbg

00:34:56

passed #282252
docker
clang_8.0_serial_dbg

00:14:01

passed #282255
docker
doc

00:01:31

passed #282243
docker cuda
gcc_5_hybrid_dbg

00:08:01

passed #282244
docker cuda
gcc_7_hybrid

00:06:26

passed #282245
docker cuda
gcc_7_serial_dbg

00:13:13

passed #282257
docker
gcc_8_hybrid_dbg_noboost

00:31:30

passed #282248
docker
gcc_9_hybrid_dbg

00:44:11

passed #282249
docker
gcc_9_hybrid_dbg_sp

00:30:39

passed #282247
docker
gcc_9_mpionly_dbg

01:01:11

passed #282246
docker
gcc_9_serial_dbg

00:40:13

passed #282235
intel docker
intel_17_hybrid_dbg

00:53:13

passed #282236
intel docker cuda
intel_18_hybrid

00:53:54

passed #282237
intel docker cuda
intel_18_serial_dbg

00:08:20

passed #282238
intel docker
intel_19_hybrid

00:53:20

passed #282241
intel docker
intel_19_hybrid_dbg

01:05:19

passed #282242
intel docker
intel_19_hybrid_dbg_sp

01:18:14

passed #282240
intel docker
intel_19_mpionly_dbg

00:55:38

passed #282239
intel docker
intel_19_serial_dbg

00:38:34

passed #282266
mac
mac_MpiOnly

01:36:24

passed #282668
mac
mac_MpiOnly_Dbg

01:40:18

passed #282264
mac
mac_Serial

01:11:04

passed #282263
mac
mac_Serial_Dbg

01:37:17

passed #282260
win
msvc-14.2_Hybrid

00:29:42

passed #282258
win
msvc-14.2_Hybrid_Dbg

00:41:35

passed #282259
win
msvc-14.2_Hybrid_SP_Dbg

00:41:55

passed #282262
win
msvc-14.2_MpiOnly_Dbg

00:38:33

passed #282261
win
msvc-14.2_Serial_Dbg

00:33:22

failed #282265
mac
mac_MpiOnly_Dbg

02:19:17