Split the AceEditor into two files and use React.Suspense

This actually increases the number of requests by one. Previously:

1. Ace library
2. Ace theme
3. Ace keybinding

This adds:

4. Our Ace React component

This is on par with what the Monaco editor has been doing. Technically
it's better for the people who use the simple editor, but probably
slightly slower for the people using the default configuration.

Author: shepmaster

ui/frontend/.eslintrc.js

@@ -60,7 +60,12 @@ module.exports = {
   },
   overrides: [
     {
-      files: ['.eslintrc.js', 'editor/SimpleEditor.tsx', 'websocketMiddleware.ts'],
+      files: [
+        '.eslintrc.js',
+        'editor/AceEditor.tsx',
+        'editor/SimpleEditor.tsx',
+        'websocketMiddleware.ts',
+      ],
       extends: ['prettier'],
     },
   ],

ui/frontend/.prettierignore

@@ -11,5 +11,6 @@ node_modules
 
 # Slowly migrate files that we've touched
 !.eslintrc.js
+!editor/AceEditor.tsx
 !editor/SimpleEditor.tsx
 !websocketMiddleware.ts