UI: Remove old icons (#16335)

* removed unsused grafana-icon classes, replaced grafana-icons with gicons

* replaced old dashboard and datasource icons with gicon, fixed so icons on plugin list are shown

* removed unsused grafana-icon classes, replaced grafana-icons with gicons

* replaced old dashboard and datasource icons with gicon, fixed so icons on plugin list are shown

* replaced fontawesome cog, eye, link and edit with gicons

* updated snapshot

* fixed color of cog in dashboard nav, removed icons from buttons, ran preitterier on some files

* changed opacity on getting started icons and fixed getting started button

* .5 -> 0.5 fix for prettier

public/app/features/dashboard/components/FolderPicker/template.html

@@ -19,7 +19,7 @@
     <button class="btn btn-inverse"
       ng-click="ctrl.createFolder($event)"
       ng-disabled="!ctrl.newFolderNameTouched || ctrl.hasValidationError">
-      <i class="fa fa-fw fa-save"></i>&nbsp;Create
+      Create
     </button>
   </div>
   <div class="gf-form" ng-if="ctrl.createNewFolder">