Add collar items to body status for mouth parts

doc/ARMOR_BALANCE_AND_DESIGN.md

@@ -563,7 +563,7 @@ RAIN_PROOF | Wont get wet in rain
 HOOD | Keeps head warm if nothing on it
 POCKETS | Keeps hands warm if they are free
 BLOCK_WHILE_WORN | Can be used to block with while worn
-COLLAR | Keeps mouth warm if not covered
+COLLAR | Keeps mouth warm if not heavily encumbered
 ONLY_ONE | Only one of this item can be worn
 ONE_PER_LAYER | Only one item can be worn on this clothing layer
 FANCY | Clothing is impractically fancy, (like a top hat)

doc/JSON_FLAGS.md

@@ -339,7 +339,7 @@ Some armor flags, such as `WATCH` and `ALARMCLOCK` are compatible with other ite
 - ```BLOCK_WHILE_WORN``` Allows worn armor or shields to be used for blocking attacks.
 - ```BULLET_IMMUNE``` Wearing an item with this flag makes you immune to bullet damage
 - ```CANT_WEAR``` This item can't be worn directly.
-- ```COLLAR``` This piece of clothing has a wide collar that can keep your mouth warm.
+- ```COLLAR``` This piece of clothing has a wide collar that can keep your mouth warm when it is mostly unencumbered.
 - ```COMBAT_TOGGLEABLE``` This item is meant to be toggled during combat. Used by NPCs to determine if they will toggle it on during combat. This only supports simple "transform" actions.
 - ```DECAY_EXPOSED_ATMOSPHERE``` Consumable will go bad once exposed to the atmosphere (such as MREs).
 - ```DEAF``` Makes the player deaf.

src/character_attire.cpp

@@ -2130,6 +2130,10 @@ void outfit::prepare_bodymap_info( bodygraph_info &info, const bodypart_id &bp,
                 covered = true;
             }
         }
+        if( !covered && bp == body_part_mouth && armor.has_flag(flag_COLLAR) && person.encumb( body_part_mouth ) < 10) {
+            // collars don't cover or encumber, but do conditionally provide warmth
+            info.worn_names.push_back( string_format( "%s (collar)", armor.tname() ) );
+        }
         if( !covered ) {
             continue;
         }