CHOP-962: per code review, comment that other code relies on "Global".

The comment advises grepping for "Global" rather than specifically pointing to
llcontrol.cpp because that's NOT the only place that relies on the name
"Global"! Besides, by the time someone does want to change the name, still
other such dependencies could've crept in.

indra/newview/llviewercontrol.cpp

@@ -83,7 +83,9 @@
 BOOL 				gHackGodmode = FALSE;
 #endif
 
-
+// Should you contemplate changing the name "Global", please first grep for
+// that string literal. There are at least a couple other places in the C++
+// code that assume the LLControlGroup named "Global" is gSavedSettings.
 LLControlGroup gSavedSettings("Global");	// saved at end of session
 LLControlGroup gSavedPerAccountSettings("PerAccount"); // saved at end of session
 LLControlGroup gCrashSettings("CrashSettings");	// saved at end of session