Implement expression in skin editor.

Http/SkinEditor/app.css

@@ -155,15 +155,32 @@ input {
 
 .t-exp {
 	border-top: solid 1px gray;
+	vertical-align: top;
 }
 
 	.t-exp.t-inline {
-		padding: 2px 4px;
+		margin: 0 2px;
+		padding: 2px;
 	}
-
+	
+	.t-exp .t-inline {
+		margin: 0 2px 2px 2px;
+	}
+	
+	.t-exp .t-statement {
+		margin: 0;
+		border: 0;
+		border-left: solid 1px red;
+		padding: 0;
+	}
+	
 	.t-exp:hover {
 		border-top: solid 3px gray;
 	}
+	
+	.t-exp .btn-add:not(:only-child) {
+		display: none;
+	}
 
 .t-input {
 	display: inline-block;