This is useful for moving functions to newer names
or newer modules/locations and retaining the old function
so that the old function proxies to the new function and
emits a deprecation warning when it is called.
Also fixes how the 'get_callable_name' needs to filter
for none, as it appears that when ran under sphinx the
'__module__' attribute is set to none and this causes
issues when joining into a string.
Change-Id: I290f1b71c141c6647da1750aec348ea590a8d9bd
f0f1fce2a2