Update styles and add task priority feature

- Changed border color from #eee to #cdcdcd in various CSS files including dropzone, mapplic, summernote, grid, and select2 to enhance UI consistency.
- Added a new task priority selection feature in the task popup, allowing users to change the priority of tasks dynamically via AJAX.
- Implemented AJAX functionality to handle task priority changes and update the task list accordingly.

libraries/framework/skin/base/buttons.less

@@ -154,7 +154,7 @@ input[type="button"] {
     text-decoration: none;
     background-color: #fbfbfb;
     border-radius: 1px;
-    border: 1px solid #EEE;
+    border: 1px solid #cdcdcd;
     border-left: 4px solid #EEE;
     -webkit-transition: opacity 0.1s ease;
     transition: opacity 0.1s ease;