fix(tooltip): dismiss tooltip on esc

Author: akashsonune

projects/element-ng/tooltip/si-tooltip.directive.ts

@@ -27,7 +27,8 @@ import { SiTooltipService, TooltipRef } from './si-tooltip.service';
     '(mouseenter)': 'show()',
     '(touchstart)': 'hide()',
     '(focusout)': 'hide()',
-    '(mouseleave)': 'hide()'
+    '(mouseleave)': 'hide()',
+    '(document:keydown.escape)': 'tooltipRef && hide()'
   }
 })
 export class SiTooltipDirective implements OnDestroy {