OHIF-333: Split Button (#1988)

* ohif-333: add component foundation

* ohif-333: add expandable content and mocked data

* ohif-333: improve ListMenu component for the new toolbar button and add radio behavior

* ohif-333: add click outside behavior and update primary and secondary props

* ohif-333: separate classes from markup

* ohif-333: fix layout issues

* ohif-333: extract window level component

* ohif-333: update component returns

* ohif-333: update chevron thickness

* ohif-333: remove is active prop

* Delete lerna-debug.log

* ohif-333: clean toolbar and use example in ui package

* ohif-333: update styles to avoid word break

* ohif-333: fix ui package build

Co-authored-by: Erik Ziegler <erik.sweed@gmail.com>
Co-authored-by: Danny Brown <danny.ri.brown@gmail.com>

platform/ui/src/components/ThumbnailTracked/ThumbnailTracked.mdx.todo

@@ -26,7 +26,7 @@ import { ThumbnailTracked } from '@ohif/ui';
         seriesNumber={4}
         numInstances={902}
         onClick={() => alert('Thumbnail was clicked!')}
-        viewportIdentificator="A"
+        viewportIdentificator={["A"]}
         isTracked={true}
         isActive={false}
       />