Better form themes (#465)

* Working on custom radius + input size

* Fix date input clear vertical align

* Moslty finished implementing small size

* Polishing larger theme

* Finish large theme

* Added size/radius options in form editor

* Darken help text, improve switch input help location

* Slight form editor improvement

* Fix styling

* Polish of the form editor

client/lib/forms/themes/CachedDefaultTheme.js

@@ -0,0 +1,21 @@
+import ThemeBuilder from './ThemeBuilder.js'
+
+const CachedDefaultTheme = (function() {
+  let instance
+
+  function createInstance() {
+    const themeBuilder = new ThemeBuilder()
+    return themeBuilder.getAllComponents()
+  }
+
+  return {
+    getInstance: function() {
+      if (!instance) {
+        instance = createInstance()
+      }
+      return instance
+    }
+  }
+})()
+
+export default CachedDefaultTheme