fix: cleanup dist folder, change README

- move images for README into docs/img
- move libs/* into utils. libs folder is copied into dist by grafana-toolkit
- remove d3-scale-chromatic sources, use it from dependencies
- update compatible versions in README
- update installation info

src/util/grafana/events/events.ts

@@ -0,0 +1,16 @@
+import { AppEvent } from './appEvents';
+
+export interface GraphHoverPayload {
+  pos: any;
+  panel: {
+    id: number;
+  };
+}
+
+export var graphHover: AppEvent<GraphHoverPayload> | string = { name: 'graph-hover' };
+export var graphHoverClear: AppEvent<any> | string = { name: 'graph-hover-clear' };
+
+export function fallbackToStringEvents() {
+  graphHover = 'graph-hover';
+  graphHoverClear = 'graph-hover-clear';
+}