RFR: Proper parsing of git diff --raw lines

[Erik Duveblad via github.com]

The pull request has been updated with additional changes.

----------------

Added commits:
 - 418494fa:	Add a test

Pull request:
https://git.openjdk.java.net/skara/pull/49

Webrevs:
 - full: https://webrevs.openjdk.java.net/skara/49/webrev.01
 - inc: https://webrevs.openjdk.java.net/skara/49/webrev.00-01

Updated full patch:
https://git.openjdk.java.net/skara/pull/49.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/49/head:pull/49