How to Regenerate Sketch File from JSON
### Description
After checking out a repository I can not see how to Regenerate the Sketch file successfully. 
I click that btn but even after waiting no sketch file appears in my repo directory.

<img width="593" alt="kactus" src="https://user-images.githubusercontent.com/232397/30388820-cc503f76-9865-11e7-9794-886e6b996c4d.png">

### Version
0.2.6

**OS version:** Sierra 10.12.6

### Steps to Reproduce

1. Clone remote repo
1. Click "Regenerate Sketch File from JSON"
1. Can not find or see the regenerated file

**Expected behavior:** Have a regenerated Sketch file from JSON

**Actual behavior:** No file created

**Reproduces how often:** 100%

### Logs
2017-09-12T23:24:10.797Z - info: [ui] Opt out reported.
2017-09-12T23:24:49.895Z - info: [ui] Executing getRemotes: git remote -v (took 3.191s)
2017-09-12T23:24:52.448Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 2.964s)
2017-09-12T23:25:42.649Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 1.272s)
2017-09-12T23:26:06.449Z - info: [ui] Executing exportCommit: git archive 6f5fb71c56613a42c6b9001855d74e4966f9354b -o /Users/UserName/Library/Application Support/Kactus/previews/1/6f5fb71c56613a42c6b9001855d74e4966f9354b.tar (took 2.203s)
2017-09-12T23:27:07.981Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 4.969s)
2017-09-12T23:27:08.036Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 2.372s)
2017-09-12T23:31:59.435Z - info: [ui] Executing exportCommit: git archive 00ea2b6b8e920c37e9bdc2dc86b874902b27b883 -o /Users/UserName/Library/Application Support/Kactus/previews/1/00ea2b6b8e920c37e9bdc2dc86b874902b27b883.tar (took 2.825s)
