Fix some issues pointed out by IDE.

* Update .gitignore to ignore .idea.
* Removed unused local variables.
* use local context and Message class instead of deprecated wfMsg* methods.
* Remove redundant px in CSS where possible.
* Combine CSS statements where possible.
* Replace b by strong.

Change-Id: I9d5ed7b7ce585a1c101044254bcbdfc33d42afc1

resources/css/ext.languagesettings.css

@@ -24,7 +24,7 @@
 	font-size: 16pt;
 	line-height: 1.5em;
 	padding-left: 6px;
-	margin-top: 0px;
+	margin-top: 0;
 	margin-bottom: 15px;
 	border-bottom: none;
 	color: #777;
@@ -33,8 +33,8 @@
 .uls-menu h3 {
 	font-size: 14pt;
 	line-height: 1.5em;
-	padding-left: 0px;
-	margin-top: 0px;
+	padding-left: 0;
+	margin-top: 0;
 	margin-bottom: 10px;
 	border-bottom: none;
 }