Switching rapidly between branches creates unwanted changes
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## Description
When switching rapidly between two branches, the state of first branch is going to over write the state of the second branch and create a pending change to commit.

## Version
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* Kactus: 0.3.6
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* Operating system: Mac 0SX 10.13.4


## Steps to Reproduce
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1. Create repo and add a sketch file.
2. Draw a rectangle in the sketch file and commit.
3. Create new branch called "color".
4. Change color of rectangle and commit.
5. In kactus, switch back and forth between the two branches quickly. After one or two back and forth, changes of one branch will have been applied to the other.

### Expected Behavior
<!-- What you expected to happen -->
Branches should not "pollute" each other. The changes in one branch should never be applied the other unless requested.

### Actual Behavior
<!-- What actually happens -->
The state of the file in one branch will overwrite the state of the Sketch file in the other branch.


## Additional Information
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### Logs
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[2018-05-15.kactus.production.log](https://github.com/kactus-io/kactus/files/2005513/2018-05-15.kactus.production.log)
