feature: tooltip in the checkbox

feature: add GridColumn.getElement
feature: column property of `contentWrap` and `maxLines`
change: line height from 24px to 18px
fix: adapt enabled after cell changed
fix: wrap issue of filter panel

lib/ui/checkbox.d.ts

@@ -14,6 +14,8 @@ interface CheckboxOptions {
     type?: string;
     /** 标签 */
     label?: string | HTMLElement;
+    /** 标签提示文本 */
+    title?: string;
     /** 是否已选中 */
     checked?: boolean;
     /** 图片高度 */