Add TOF v20d the double wall for mCBM in 2021, refs #1593

setup/setup_mcbm_beam_2021_03.C

@@ -61,7 +61,8 @@ void setup_mcbm_beam_2021_03()
 //  TString muchGeoTag      = "v19a_mcbm";    // need 3 layers and RPC here
   TString trdGeoTag       = "v20b_mcbm";    // 2021 // 2 TRD modules
 //  TString trdGeoTag       = "v18q_mcbm";    // 2 TRD modules 
-  TString tofGeoTag       = "v20c_mcbm";
+  TString tofGeoTag       = "v20c_mcbm";    // 1st layer of TOF modules
+//  TString tofGeoTag       = "v20d_mcbm";    // 2nd layer of 3x M6 modules added
   TString richGeoTag      = "v20d_mcbm";    // geometry provided by RICH group
   TString psdGeoTag       = "v20a_mcbm";    // at 25 degree, below the beampipe
   // ------------------------------------------------------------------------

tof/tof_v20d_mcbm.geo.info

+#
+##   tof_v20d_mcbm information file
+#
+
+# created 20200527
+
+# TOF setup
+
+# envelope
+   0.00 cm   start of TOF (z)
+ 416.50 cm   end   of TOF (z)
+
+# central tower position
+ 400.00 cm   center of staggered, front RPC cell at x=0
+