Really really slow cloning a big repo
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### Description

[Whenever I click on anything within the UI, it freezes]

### Version

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**Kactus version:** 0.2.12]

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**OS version:** [0.11.6 (15G1510]

### Steps to Reproduce

1. [Download big repo]
1. [Click on a layer]
1. [wait and it should freeze]

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**Expected behavior:** [Be as smooth as a smaller repo that I have]

**Actual behavior:** [Sluggish and freezes. Cant see files on the right]

**Reproduces how often:** [100%]

### Logs
%P -z --no-color -- (took 104.490s)
2017-11-09T13:31:19.507Z - info: [ui] Executing getAuthorIdentity: git var GIT_AUTHOR_IDENT (took 204.718s)
2017-11-09T13:31:19.508Z - info: [ui] Executing getRemotes: git remote -v (took 204.723s)
2017-11-09T13:31:19.528Z - info: [ui] Executing getCommits: git log HEAD --date=raw --max-count=100 --pretty=%H%x1F%s%x1F%b%x1F%an <%ae> %ad%x1F%P -z --no-color -- (took 2.243s)
2017-11-09T13:31:19.529Z - info: [ui] Executing getHEADsha: git rev-parse HEAD (took 100.258s)
2017-11-09T13:31:22.807Z - info: [ui] Executing exportCommit: git archive 2697355b4c74345a9dbfee2826073ab39dc9a34a -o /Users/grhall/Library/Application Support/Kactus/previews/2/2697355b4c74345a9dbfee2826073ab39dc9a34a.tar (took 3.268s)
2017-11-09T13:31:22.811Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 4.822s)
2017-11-09T13:31:29.379Z - info: [ui] Executing getRemotes: git remote -v (took 6.580s)
2017-11-09T13:31:29.380Z - info: [ui] Executing getAuthorIdentity: git var GIT_AUTHOR_IDENT (took 6.578s)
2017-11-09T13:31:29.407Z - info: [ui] Executing getStatus: git status --untracked-files=all --branch --porcelain=2 -z (took 9.924s)
2017-11-09T13:37:04.575Z - info: [ui] Executing exportCommit: git archive 2697355b4c74345a9dbfee2826073ab39dc9a34a -o /Users/grhall/Library/Application Support/Kactus/previews/2/2697355b4c74345a9dbfee2826073ab39dc9a34a.tar (took 105.322s
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