RFR: Allow output path to be created with arbitrary directory nesting

[Leo Korinth via github.com]

createDirectories works like ```mkdir -p``` and the _exists_ check is no longer needed

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Commits:
 - 3c40edbf:	Allow output path to be created with arbitrary directory nesting

Pull request:
https://git.openjdk.java.net/skara/pull/76

Webrev:
https://webrevs.openjdk.java.net/skara/76/webrev.00

Patch:
https://git.openjdk.java.net/skara/pull/76.diff

Fetch command:
git fetch https://git.openjdk.java.net/skara pull/76/head:pull/76