Merge pull request #87 from apostolos/patch-1

Update freezing defaults in flow defs

src/immer.js.flow

@@ -34,7 +34,7 @@ declare export default function produce<S>(
  * Automatically freezes any state trees generated by immer.
  * This protects against accidental modifications of the state tree outside of an immer function.
  * This comes with a performance impact, so it is recommended to disable this option in production.
- * It is by default enabled.
+ * By default it is turned on during local development, and turned off in production.
  */
 declare export function setAutoFreeze(autoFreeze: boolean): void