Merge branch 'karapiperis/minor_change_to_SB_VR_config_file' into 'master'

Small addition to SB example VR config file, without which VR does not run on...

See merge request !2118

examples/SantaBarbara/SantaBarbara-256/velociraptor_cfg.cfg

@@ -41,6 +41,9 @@ Significance_level=1.0 #how significant a substructure is relative to Poisson no
 Length_unit_to_kpc=1000. #conversion of output length units to kpc
 Velocity_to_kms=1.0      #conversion of output velocity units to km/s
 Mass_to_solarmass=1e+10  #conversion of output mass units to solar masses
+Star_formation_rate_to_solarmassperyear=1.0
+Metallicity_to_solarmetallicity=1.0
+Stellar_age_to_yr=1.0
 
 # units conversion from input to desired internal unit.
 # These should be set to 1 unless a conversion is expected.