Import pylockfile

This is an import of the pylockfile project:

  https://pypi.python.org/pypi/lockfile
  https://github.com/smontanaro/pylockfile

We are taking over its maintenance per request of Skip Montanaro:

  https://github.com/smontanaro/pylockfile/issues/11#issuecomment-45634012

The initial import should fail with some of the tests target, but we'll
fix them with one giant first commit.

Blueprint: pylockfile-adoption

Change-Id: Ie004ea627ddff75cb84ba6d774198de37b7d45ce
Merge "Import pylockfile"