Seeing an error messsage with the repo.
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### Description

[getting an error every time I go to the main screen of my repo.]
<img width="867" alt="screenshot 2017-07-21 09 47 31" src="https://user-images.githubusercontent.com/3729049/28468835-c687960c-6df9-11e7-9776-08e96b6b7d69.png">


### Version

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**Kactus version:** [0.1.12]

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**OS version:** [10.12.5]

### Steps to Reproduce

1. [Open repo]
2. [Go to the changes tab]

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**Expected behavior:** [More detailed information about the error that I can understand and how to fix it.]

**Actual behavior:** [What actually happened]

**Reproduces how often:** [What percentage of the time does it reproduce? 100%]

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#### Additional Information

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