Replace locks and replace with fasteners library provides ones

The fasteners library (extracted from this library and a couple other
variations) provides the interprocess lock logic and the reader writer
lock logic so we can remove the local version and we can just use it
from that library instead.

The tests that were ensuring the internals of this file lock have
now moved to the repo where that library is (for the time being),
currently travis is testing that repo against py2.6, py2.7 and py3.4.

https://github.com/harlowja/fasteners/tree/master/fasteners/tests

Docs also exist at:

http://fasteners.readthedocs.org/en/latest/

Change-Id: I98565b22e68358efe28fea62f74f8ebfcc438ff7