新增大题时，前端增加题号输入校验

stmms-web/src/main/webapp/WEB-INF/views/modules/exam/groupAdd.jsp

@@ -46,7 +46,7 @@
         <div class="control-group">
             <label class="control-label">题号</label>
             <div class="controls">
-                <form:input path="number" htmlEscape="false" maxlength="10" class="required"/>
+                <form:input path="number" htmlEscape="false" maxlength="10" min="1" class="required digits"/>
             </div>
         </div>
 		<div class="control-group">