Merge remote-tracking branch 'prototech/ticket/11928' into develop

# By Cesar G
# Via Cesar G
* prototech/ticket/11928:
  [ticket/11928] Javascript requires camel case.
  [ticket/11928] Rename loadingAlert to loading_indicator.
  [ticket/11928] Make sure the indicator is on top of other elements.
  [ticket/11928] Replace AJAX loading popup with animation.

phpBB/styles/prosilver/theme/colours.css

@@ -1104,6 +1104,11 @@ input.disabled {
 	background-color: #000000;
 }
 
+#loading_indicator {
+	background-color: #000000;
+	background-image: url("./images/loading.gif");
+}
+
 #notification_list ul li {
 	border-bottom-color: #B9B9B9;
 }

phpBB/styles/prosilver/theme/common.css

@@ -821,6 +821,21 @@ li.pagination ul {
 	opacity: 0.5;
 }
 
+#loading_indicator {
+	background: center center no-repeat;
+	border-radius: 5px;
+	display: none;
+	opacity: 0.8;
+	margin-top: -50px;
+	margin-left: -50px;
+	height: 50px;
+	width: 50px;
+	position: fixed;
+	left: 50%;
+	top: 50%;
+	z-index: 51;
+}
+
 /* Miscellaneous styles
 ---------------------------------------- */
 #forum-permissions {