Added "extra" damage type

Takes on the same damage type as the last damage applied during the
same action, otherwise deals "extra" damage

app/imports/api/engine/computation/utility/getEffectivePropTags.js

@@ -0,0 +1,17 @@
+export default function getEffectivePropTags(prop) {
+  if (!prop.tags) return [];
+  const tags = [...prop.tags];
+  // Tags for the property type, separate #damage from #healing
+  if (prop.type === 'damage' && prop.damageType === 'healing') {
+    tags.push('#healing');
+  } else {
+    tags.push(`#${prop.type}`);
+  }
+
+  // Tags for some string properties
+  if (prop.damageType) tags.push(prop.damageType);
+  if (prop.skillType) tags.push(prop.skillType);
+  if (prop.attributeType) tags.push(prop.attributeType);
+  if (prop.reset) tags.push(prop.reset);
+  return tags;
+}