Apple icons

Related to issue #608 

Add the apple icons (used to appear when adding the web page to the home screen, instead of a screen shot). In my opinion, three different instances needed to be adaped, the api doc, the extended tooltips, and the lubis image (which are not dependent on extended tooltip). Do I forget smthing ?

[Test link extendedTooltip ](http://mf-chsdi3.dev.bgdi.ch/kan_apple_icons/rest/services/ech/MapServer/ch.babs.kulturgueter/9221/extendedHtmlPopup?lang=de)

[Test link Luftbilder] (http://mf-chsdi3.dev.bgdi.ch/kan_apple_icons/luftbilder/viewer.html?lang=fr&layer=ch.swisstopo.lubis-luftbilder_schwarzweiss&title=No+de+l%27image&height=5952&width=5954&bildnummer=19280250012535&datenherr=swisstopo&x=1162.79&y=3451.62&zoom=1&rotation=0)

[Test link Api doc] (http://mf-chsdi3.dev.bgdi.ch/kan_apple_icons)

Please test on apple devices ;)