fix(core): update

ts/index.ts

@@ -1,21 +1,30 @@
 import { CssManager } from './dees-element.classes.cssmanager';
 import * as plugins from './dees-element.plugins';
 
+// lit exports
 export {
-  customElement,
-  property,
   html,
   TemplateResult,
   css,
   unsafeCSS,
-  state
-} from 'lit-element';
+} from 'lit';
 
+export {
+  customElement,
+  property,
+  state
+} from 'lit/decorators'
+
+// domtools exports
 import * as domtools from '@designestate/dees-domtools';
 export {
   domtools
 }
 
+// DeesElements exports
 export { DeesElement } from './dees-element.classes.dees-element';
 
+/**
+ * a singleton instance of CssManager
+ */
 export const cssManager = new CssManager();