Core: Add support for hex colors with alpha transparency - short version

This adds support for the short version of hex colors with alpha transparency:

  eg. #09be (is #09b color with e alpha)

However, jquery-color would convert this hex value to an rgb value
losing the alpha transparency:

  eg. rgb(0, 153, 187)

Ref #129
Ref #126

Author: mgol

jquery.color.js

@@ -76,6 +76,19 @@
 			}
 		}, {
 
+			// this regex ignores A-F because it's compared against an already lowercased string
+			re: /#([a-f0-9])([a-f0-9])([a-f0-9])([a-f0-9])/,
+			parse: function( execResult ) {
+				return [
+					parseInt( execResult[ 1 ] + execResult[ 1 ], 16 ),
+					parseInt( execResult[ 2 ] + execResult[ 2 ], 16 ),
+					parseInt( execResult[ 3 ] + execResult[ 3 ], 16 ),
+					( parseInt( execResult[ 4 ] + execResult[ 4 ], 16 ) / 255 )
+						.toFixed( 2 )
+				];
+			}
+		}, {
+
 			// this regex ignores A-F because it's compared against an already lowercased string
 			re: /#([a-f0-9])([a-f0-9])([a-f0-9])/,
 			parse: function( execResult ) {

test/unit/color.js

@@ -192,6 +192,28 @@ parseTest( "#77777700", {
 	alpha: 0
 } );
 
+parseTest( "#7776", {
+	expect: 4,
+	red: 119,
+	green: 119,
+	blue: 119,
+	alpha: 0.4
+} );
+parseTest( "#777F", {
+	expect: 4,
+	red: 119,
+	green: 119,
+	blue: 119,
+	alpha: 1
+} );
+parseTest( "#7770", {
+	expect: 4,
+	red: 119,
+	green: 119,
+	blue: 119,
+	alpha: 0
+} );
+
 var fiftypercent = {
 	expect: 4,
 	red: 127,