feat(popover): Add click-to-dismiss popover template to core

Packages/ohif-core/client/components/bootstrap/index.js

@@ -36,3 +36,4 @@ import './input/text.html';
 import './notification';
 
 import './popover/form.html';
+import './popover/popoverSimple.html';

Packages/ohif-core/client/components/bootstrap/popover/popoverSimple.html

@@ -0,0 +1,4 @@
+<template name="popoverSimple">
+    {{#if this.message}}{{this.message}}{{/if}}
+    {{>UI.contentBlock}}
+</template>