Checkboxes in the settings panel don't remember the last used settings.
**Which version of the plugin are you using?**
[3.0.3 ] Data Populator for Sketch

**Describe the bug**
In the settings panel the Data Option checkboxes don't remember the last used settings which results in them not working correctly when re-populating. Specifically in my case the random results wasn't working when the random checkbox appeared to be toggled on. I had to toggle the random off then on again to get random working. 

**Expected behavior**
Expect the last used settings for data option to be what I had previously selected.


**Environment (please complete the following information):**
 - macOS Version: [macOS High Sierra 10.14.1]
 - Sketch Version [Sketch 52.4]
 - Plugin Version [e.g. 3.0.3]
