Added comment in config/default and removed empty character error.

config/default.cfg

-# |  (C) 2006-2019 Potsdam Institute for Climate Impact Research (PIK)
+# |  (C) 2006-2019 Potsdam Institute for Climate Impact Research (PIK)
 # |  authors, and contributors see CITATION.cff file. This file is part
 # |  of REMIND and licensed under AGPL-3.0-or-later. Under Section 7 of
 # |  AGPL-3.0, you are granted additional permissions described in the
@@ -145,6 +145,7 @@ cfg$gms$CDR <- "DAC"        # def = DAC
 
 # ***---------------------    35_transport    ----------------------------------------
 # * (complex):  transport realization including electricity in the transport sector (*RP*)
+# * (edge_esm): transport realization with detailed modes/vehicles representation (*AD*, *MR*)
 cfg$gms$transport <- "complex"           # def = complex
 
 # ***---------------------    36_buildings    ---------------------------------