Negative padding found. Likely a problem in geometry of group error
### How did it happen?
1. Committing sketch file
2. I ticked `pretty diffs`
3. and error happens
### Error log

```
2016-10-03 15:33:25.300 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1f07a50> Page 1 (E4772E9F-A62C-483C-982C-A68E65CA5801)
2016-10-03 15:33:25.303 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1c931f0> Page 1 (8375CFAE-6493-480B-BEE4-C832BE0EBCEB)
2016-10-03 15:33:25.305 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1d610a0> Page 1 (FF67D365-BC73-482D-B88D-4A333D911216)
2016-10-03 15:33:25.307 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1d81a90> Page 1 (2D532391-CFEC-4591-89AB-B603DCC1F02E)
2016-10-03 15:33:25.310 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1d98ed0> Page 1 (AFB47E60-F11D-44E0-837D-2773A89ECAE0)
2016-10-03 15:33:25.312 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1e389c0> Page 1 (65480237-9B45-49F4-A7A9-919B46C11AF7)
2016-10-03 15:33:25.314 sketchtool[34249:265667] Negative padding found. Likely a problem in geometry of group: <MSImmutableLayerGroup: 0x7fd9c1da9940> Page 1 (5D1AA18C-6767-4FEF-B546-39D3DF8D3CA6)
warning: You ran 'git add' with neither '-A (--all)' or '--ignore-removal',
whose behaviour will change in Git 2.0 with respect to paths you removed.
Paths like '.exportedArtboards/Project/01 - Artboard1.png' that are
removed from your working tree are ignored with this version of Git.
```

The error does not happen when i uncheck the `pretty diffs` option

Tried googling around and can't find a solution to this.

May i know if there's any workaround ?

Cheers
