prevent traceback in upgrade function

src/common/optparser.py

@@ -760,6 +760,8 @@ class OptionsParser:
 			'urlmsgcolor': ['#0000ff', '#204a87'],
 			'gc_nicknames_colors': ['#a34526:#c000ff:#0012ff:#388a99:#045723:#7c7c7c:#ff8a00:#94452d:#244b5a:#32645a', '#4e9a06:#f57900:#ce5c00:#3465a4:#204a87:#75507b:#5c3566:#c17d11:#8f5902:#ef2929:#cc0000:#a40000']}
 		for c in vals:
+			if c not in self.old_values:
+				continue
 			val = self.old_values[c]
 			if val == vals[c][0]:
 				# We didn't change default value, so update it with new default
@@ -770,6 +772,8 @@ class OptionsParser:
 		vals = {'statusmsgcolor': ['#73d216', '#4e9a06'],
 			'outmsgtxtcolor': ['#a2a2a2', '#555753']}
 		for c in vals:
+			if c not in self.old_values:
+				continue
 			val = self.old_values[c]
 			if val == vals[c][0]:
 				# We didn't change default value, so update it with new default