improve popup close button, get rid of the image, closes #631

dist/leaflet.css

@@ -305,15 +305,20 @@
 	-o-transform: rotate(45deg);
 	transform: rotate(45deg);
 	}
-.leaflet-popup-close-button {
+.leaflet-container a.leaflet-popup-close-button {
 	position: absolute;
-	top: 8px;
-	right: 8px;
-
-	width: 10px;
-	height: 10px;
-
-	overflow: hidden;
+	top: 3px;
+	right: 3px;
+	text-align: center;
+	width: 24px;
+	height: 24px;
+	font: 16px/24px Tahoma, Verdana, sans-serif;
+	color: #ccc;
+	text-decoration: none;
+	font-weight: bold;
+	}
+.leaflet-container a.leaflet-popup-close-button:hover {
+	color: #999;
 	}
 .leaflet-popup-content p {
 	margin: 18px 0;
@@ -363,6 +368,3 @@
 .leaflet-popup-content {
 	font: 12px/1.4 "Helvetica Neue", Arial, Helvetica, sans-serif;
 	}
-.leaflet-popup-close-button {
-	background: white url(images/popup-close.png);
-	}

src/layer/Popup.js

@@ -107,6 +107,7 @@ L.Popup = L.Class.extend({
 		if (this.options.closeButton) {
 			closeButton = this._closeButton = L.DomUtil.create('a', prefix + '-close-button', container);
 			closeButton.href = '#close';
+			closeButton.innerHTML = '×';
 
 			L.DomEvent.on(closeButton, 'click', this._onCloseButtonClick, this);
 		}