Editor embeds (#680)

- [x] Make deleting an embed easier
- [x] Add document level ability to disable embeds
- [x] Add team level ability to disable embeds
- [x] GitHub
- [x] Numeracy
- [x] Mode Analytics
- [x] Figma
- [x] Airtable
- [x] Vimeo
- [x] RealtimeBoard
- [x] Loom
- [x] Lucidcharts
- [x] Framer
- [x] InVision
- [x] Typeform
- [x] Marvel
- [x] Spotify
- [x] Codepen
- [x] Trello

app/embeds/Lucidchart.js

@@ -0,0 +1,26 @@
+// @flow
+import * as React from 'react';
+import Frame from './components/Frame';
+
+const URL_REGEX = /^https:\/\/(www\.)?lucidchart.com\/documents\/(embeddedchart|view)\/([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12})(?:\/.*)?$/;
+
+type Props = {
+  url: string,
+  matches: string[],
+};
+
+export default class Lucidchart extends React.Component<Props> {
+  static ENABLED = [URL_REGEX];
+
+  render() {
+    const { matches } = this.props;
+    const chartId = matches[3];
+
+    return (
+      <Frame
+        src={`http://lucidchart.com/documents/embeddedchart/${chartId}`}
+        title="Lucidchart Embed"
+      />
+    );
+  }
+}