Updated Loging form:

Display invalid credentials message inside the primary-tabs div.
Added support to submit the form using <Enter>.

modules/basic_auth/site/templates/block_login.tpl

@@ -5,12 +5,12 @@
 			<div>	
 			    <form name="cms_basic_auth" action method="POST">
 					<div>
-						<input type="text" name="username" required>
+						<input type="text" name="username" id="username" required>
 						<label>Username</label>
 					</div>
 										
 					<div>
-						<input  type="password" name="password" required>
+						<input  type="password" name="password"  id="password" required>
 						<label>Password</label>
 					</div>