Merge pull request #3487 from xiaofengsha/pr007

rate组件添加allowClear属性，通过点击可以把当前评分清零

src/components/rate/rate.vue

@@ -45,6 +45,10 @@
             },
             name: {
                 type: String
+            },
+            clearable: {
+                type: Boolean,
+                default: false
             }
         },
         data () {
@@ -123,8 +127,13 @@
             },
             handleClick (value) {
                 if (this.disabled) return;
-//                 value++;
+                //value++;
                 if (this.isHalf) value -= 0.5;
+
+                if(this.clearable && Math.abs(value - this.currentValue) < 0.01) {
+                    value = 0;
+                }
+
                 this.currentValue = value;
                 this.$emit('input', value);
                 this.$emit('on-change', value);