Patch attached that removes the misleading "convenience" functions,
replacing them with explicit imports of the appropriate names.

The patch also adds docstrings to some of the original class definitions
that were missing them.

No changes were needed to the multiprocessing tests - they all still
passed with this change, and the docs are still accurate as well (I
would actually say this change makes the docs MORE accurate).

Python 2.6b3+ (trunk:66083, Aug 31 2008, 19:00:32)
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import multiprocessing as mp
>>> isinstance(mp.Lock(), mp.Lock)
True
>>> mp.Lock.__name__
'Lock'
>>> mp.Lock.__module__
'multiprocessing.synchronize'