Clarify locked decorator is for instance methods

Make it clear when reading the lock utils code that the
locked decorator will only currently work with instance
methods by removing the usage of 'args[0]' and renaming
this variable to 'self' and adjusting the docstring.

Once the wrapt module is approved and we are able to use
it in taskflow, we can refactor the function to be correct
with regards to classmethods.

Change-Id: Ic33eb9e47679d2105654634469dd6d305d38b2e0
Fix traces left in zookeeper

We currently are leaving the root node in zookeeper
whenever this test is ran, we should instead be removing
the full directory and any children to avoid leaving
test data behind in zookeeper (aka, cleanup our dirty
laundry).

Fixes bug 1330807

Change-Id: I56d9dabd9926463506e1710ddf0a6c4831d5dc57
Merge "Clarify locked decorator is for instance methods"
Merge "Fix traces left in zookeeper"