Friendly Fire support L4D(2) games. (#1530)

Support L4D(2) Friendly Fire In Basetriggers.sp #1522

- Games have cvar mp_friendlyfire min. and max. bounds set to 1
- Removing mp_friendlyfire lower bound and set to 0, cvar have no purpose on friendly fire damage.
- FF works from z_difficulty and each difficult level have FF damage ration cvars:
survivor_friendly_fire_factor_easy
survivor_friendly_fire_factor_normal
survivor_friendly_fire_factor_hard
survivor_friendly_fire_factor_expert

Update added PRINT_TO_ things from previous update.

Co-authored-by: Bacardi <>

translations/basetriggers.phrases.txt

@@ -20,7 +20,13 @@
 	{
 		"en"		"Friendly Fire is disabled."
 	}
-	
+
+	"Friendly Fire Percent"
+	{
+		"#format"	"{1:0.0f}"
+		"en"		"Friendly Fire is {1}%."
+	}
+
 	"Current Map"
 	{
 		"#format"		"{1:s}"