Move keyboard shortcuts to modal. Add ? shortcut

frontend/components/KeyboardShortcuts/KeyboardShortcuts.js

@@ -0,0 +1,23 @@
+// @flow
+import React from 'react';
+import Flex from 'components/Flex';
+import HelpText from 'components/HelpText';
+import HtmlContent from 'components/HtmlContent';
+import flatpages from 'static/flatpages';
+import { convertToMarkdown } from 'utils/markdown';
+
+const htmlContent = convertToMarkdown(flatpages.keyboard);
+
+function KeyboardShortcuts() {
+  return (
+    <Flex column>
+      <HelpText>
+        Abstract is designed to be super fast. All of your usual keyboard
+        shortcuts work here.
+      </HelpText>
+      <HtmlContent dangerouslySetInnerHTML={{ __html: htmlContent }} />
+    </Flex>
+  );
+}
+
+export default KeyboardShortcuts;