Hygiene: Remove unused directory

Let's not use old unused things lying around... it just confuses
people.

Change-Id: I30cecb58fbdce0129e0385be3680ca4a2c6c36f8

modules/oldicons/icons.css

@@ -1,52 +0,0 @@
-.mw-echo-icon {
-	width: 42px;
-	height: 42px;
-	float: left;
-	margin-right: 5px;
-	background: no-repeat center left;
-}
-
-.mw-echo-icon-placeholder {
-	/* @embed */
-	background-image: url(placeholder.png);
-}
-
-.mw-echo-icon-chat {
-	/* @embed */
-	background-image: url(chat.png);
-}
-
-.mw-echo-icon-w {
-	/* @embed */
-	background-image: url(W.png);
-}
-
-.mw-echo-icon-revert {
-	/* @embed */
-	background-image: url(revert.png);
-}
-
-.mw-echo-icon-checkmark {
-	/* @embed */
-	background-image: url(tick.png);
-}
-
-.mw-echo-icon-trash {
-	/* @embed */
-	background-image: url(trash.png);
-}
-
-.mw-echo-icon-gift {
-	/* @embed */
-	background-image: url(gift.png);
-}
-
-.mw-echo-icon-heart {
-	/* @embed */
-	background-image: url(heart.png);
-}
-
-.mw-echo-icon-people {
-	/* @embed */
-	background-image: url(people.png);
-}