title: Collect all changed files and commit after merged
body: <p>I have master look like</p>
  <pre><code>|
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  abcd3    Commit3 (file A, B)
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  abcd2    Commit2 (file C, D)
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  abcd1    Commit1 (file E)
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  </code></pre>
  <p>and in my feature branch</p>
  <pre><code>xyz1     MyCommit (file A, B)
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  abcd1    Commit1 (file E)
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  </code></pre>
  <p>When I merge master -&gt; feature, it conflict. I resolved and have</p>
  <pre><code>xyz3     ResolveConflictAndMyNewCommit (file X, Y)
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  xyz2     Merge branch master into feature
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  xyz1     MyCommit (file A, B)
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  abcd1    Commit1 (file E)
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  </code></pre>
  <p>So I want my feature branch now look like</p>
  <pre><code>|
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  xyz      MyCommit (file A, B, X, Y)
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  abcd3    Commit3 (file A, B)
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  abcd2    Commit2 (file C, D)
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  abcd1    Commit1 (file E)
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  </code></pre>
  <p>Does git have command for this case? I tried squash but still can't make my feature branch look like result. Beside that feature branch has been pushed, I need a solution to clear history in this branch, thank you!!!</p>