FIXED #221 - Reenable wireless on limit adjustment

* Added FakeUci to make testing features which change config easier (works well with mock library)
*  Refactored routerapi/update_setting
   * is importable (for test)
   * defines and runs a main and executes on __name__ condition.
* Refactored routerapi/accumulate_bytes
  * is importable (for test)
   * defines and runs a main and executes on __name__ condition.
*extracted a script for running unit tests (if been using ```watch scripts/unit``` to continuously run)