Update singleLineMenu to support ESC escape key

lib/singleLineMenu.js

@@ -44,7 +44,8 @@ var defaultKeyBindings = {
 	TAB: 'cycleNext' ,
 	SHIFT_TAB: 'cyclePrevious' ,
 	HOME: 'first' ,
-	END: 'last'
+	END: 'last',
+	ESCAPE: 'escape'
 } ;
 
 
@@ -60,6 +61,7 @@ var defaultKeyBindings = {
 			* style `function` the style of unselected items, default to `term`
 			* selectedStyle `function` the style of the selected item, default to `term.dim.blue.bgGreen`
 			* keyBindings `Object` overide default key bindings
+			* cancelable `boolean` if ESCAPE is pressed, it exits, calling the callback with undefined values
 			* exitOnUnexpectedKey `boolean` if an unexpected key is pressed, it exits, calling the callback with undefined values
 		* callback( error , response ), where:
 			* error
@@ -69,6 +71,7 @@ var defaultKeyBindings = {
 				* x `number` the x coordinate of the selected menu item (the first character)
 				* y `number` the y coordinate of the selected menu item (same coordinate for all items since it's a single line menu)
 				* unexpectedKey `string` when 'exitOnUnexpectedKey' option is set, this contains the key that produced the exit
+				* canceled `bool` when 'cancelable' option is set, this is set to true
 */
 module.exports = function singleLineMenu( menuItems_ , options , callback ) {
 	if ( arguments.length < 1 ) { throw new Error( '[terminal] singleLineMenu() needs at least an array of menuItems' ) ; }
@@ -293,7 +296,14 @@ module.exports = function singleLineMenu( menuItems_ , options , callback ) {
 				if ( selectedPage < menuPages.length - 1 ) { selectedPage ++ ; selectedIndex = 0 ; }
 				redraw() ;
 				break ;
-
+			case 'escape' :
+				if ( options.cancelable ) {
+					cleanup( undefined , { canceled: true } ) ;
+				}
+				if ( options.exitOnUnexpectedKey ) {
+					cleanup( undefined , { unexpectedKey: key , unexpectedKeyData: data } ) ;
+				}
+				break ;
 			default :
 				if ( options.exitOnUnexpectedKey ) {
 					cleanup( undefined , { unexpectedKey: key , unexpectedKeyData: data } ) ;