using single link.svg from api and use it by default for all link* buttons

api/js/etemplate/Et2Button/ButtonMixin.ts

@@ -38,6 +38,7 @@ export const ButtonMixin = <T extends Constructor>(superclass : T) => class exte
 		cancelled: /no(&|\]|$)/,
 		ok: /ok(&|\]|$)/,
 		close: /close(&|\]|$)/,
+		link: /link(&|\]|_|$)/,
 		add: /(add(&|\]|$)|create)/	// customfields use create*
 	};
 

filemanager/templates/default/images/link.svg

@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 15.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<svg version="1.1" id="Ebene_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 width="32px" height="32px" viewBox="0 0 32 32" enable-background="new 0 0 32 32" xml:space="preserve">
-<path fill="#696969" d="M11.719,25.389L10.1,26.997c-1.404,1.391-3.687,1.393-5.089,0c-0.675-0.67-1.045-1.559-1.045-2.504
-	c0-0.944,0.371-1.834,1.045-2.502l5.96-5.914c1.235-1.225,3.559-3.028,5.252-1.349c0.777,0.771,2.033,0.767,2.803-0.01
-	c0.772-0.777,0.768-2.032-0.01-2.804c-2.878-2.857-7.134-2.329-10.839,1.347l-5.96,5.915C0.788,20.596,0,22.484,0,24.493
-	c0,2.01,0.788,3.897,2.218,5.317C3.689,31.271,5.622,32,7.555,32c1.934,0,3.867-0.729,5.339-2.19l1.621-1.608
-	c0.777-0.771,0.781-2.026,0.009-2.804C13.753,24.62,12.497,24.617,11.719,25.389z M29.781,2.417
-	c-3.092-3.068-7.415-3.234-10.276-0.394l-2.02,2.003c-0.776,0.771-0.782,2.027-0.01,2.803c0.772,0.777,2.026,0.781,2.805,0.01
-	l2.017-2.002c1.483-1.472,3.425-0.862,4.692,0.394c0.674,0.67,1.044,1.559,1.044,2.503c0,0.945-0.37,1.835-1.044,2.503l-6.359,6.308
-	c-2.906,2.885-4.271,1.531-4.853,0.953c-0.777-0.771-2.032-0.767-2.804,0.01c-0.771,0.778-0.767,2.034,0.01,2.805
-	c1.334,1.325,2.859,1.981,4.456,1.981c1.955,0,4.021-0.985,5.985-2.936l6.358-6.308C31.212,11.633,32,9.744,32,7.735
-	S31.212,3.838,29.781,2.417z"/>
-</svg>