Fix action descriptions not appearing

src/components/ActionButton.vue

@@ -1,5 +1,5 @@
 <template>
-  <button @focus="describe" class="action-button" @click="execute">
+  <button @focus="describe" @mouseover="describe" @mouseleave="undescribe" class="action-button" @click="execute">
     <div class="action-title">{{ action.name }}</div>
     <div class="action-desc">{{ action.desc }}</div>
   </button>
@@ -10,6 +10,7 @@
 import { Component, Prop, Vue, Watch, Emit } from 'vue-property-decorator'
 import { Action, GroupAction } from '@/game/combat'
 import { Creature } from '@/game/creature'
+import { nilLog } from '@/game/interface'
 
 @Component({})
 export default class ActionButton extends Vue {
@@ -44,6 +45,11 @@ export default class ActionButton extends Vue {
       this.$emit('described', this.action.describe(this.user, this.target))
     }
   }
+
+  @Emit("undescribe")
+  undescribe () {
+    this.$emit('described', nilLog)
+  }
 }
 
 </script>