SaveTool: add "unequip" button to shield parts and BL projectiles.

It doesn't actually unequip them (the game has no concept of that,
unlike accessories), but replaces the ID with one that doesn't exist.

src/Mass/Mass_Armour.cpp

@@ -130,7 +130,10 @@ auto Mass::writeArmourPart(ArmourSlot slot) -> bool {
 
     for(UnsignedInt i = 0; i < armour_array->items.size(); i++) {
         part_prop = armour_array->at<GenericStructProperty>(i);
-        if(slot_str != part_prop->at<StringProperty>("Slot_3_408BA56F4C9605C7E805CF91B642249C"_s)->value) {
+        if(slot_str == part_prop->at<ByteProperty>("Slot_3_408BA56F4C9605C7E805CF91B642249C"_s)->enumValue) {
+            break;
+        }
+        else {
             part_prop = nullptr;
         }
     }

src/SaveTool/SaveTool_MassViewer_Weapons.cpp

@@ -389,8 +389,8 @@ void SaveTool::drawWeaponEditor(Weapon& weapon) {
             weapon.damageType = DamageType::Freeze;
         }
         ImGui::SameLine();
-        if(ImGui::RadioButton("Shock##Shock", weapon.damageType == DamageType::Freeze)) {
-            weapon.damageType = DamageType::Freeze;
+        if(ImGui::RadioButton("Shock##Shock", weapon.damageType == DamageType::Shock)) {
+            weapon.damageType = DamageType::Shock;
         }
     }
 
@@ -429,12 +429,26 @@ void SaveTool::drawWeaponEditor(Weapon& weapon) {
                 _selectedWeaponPart = 0;
             }
             ImGui::SameLine();
-            ImGui::RadioButton(std::to_string(i + 1).c_str(), &_selectedWeaponPart, i);
+            ImGui::RadioButton(std::to_string(i).c_str(), &_selectedWeaponPart, i);
         }
 
         auto& part = weapon.parts[_selectedWeaponPart];
 
         ImGui::Text("ID: %i", part.id);
+        if(weapon.type == WeaponType::Shield ||
+           (weapon.type == WeaponType::BulletLauncher && _selectedWeaponPart != 0))
+        {
+            ImGui::SameLine();
+            if(ImGui::SmallButton("Unequip")) {
+                part.id = -1;
+            }
+            if(weapon.type == WeaponType::Shield && _selectedWeaponPart == 0) {
+                drawTooltip("This will make the whole shield and its accessories invisible.");
+            }
+            else {
+                drawTooltip("This will make accessories invisible as well.");
+            }
+        }
 
         if(ImGui::BeginChild("##PartDetails", {0.0f, 0.0f}, true)) {
             ImGui::TextUnformatted("Styles:");