Add context manager section

Also realized that the __init__ section is not pubished in sphinx,
instead the class docstring is treated as the initialzier docstring.
So, future work to sift through and move them all.

README.rst

@@ -275,6 +275,31 @@ More examples can be found in the
 `examples <https://github.com/stealthycoin/lynk/tree/master/examples>`_
 directory in the source repo.
 
+
+Context manager
+---------------
+
+In the above example we manually call ``acquire()`` and ``release()``. This depends on no
+exceptions ocurring, and would generally be safer in a ``try: finally:`` block. For
+convenience the :class:`lynk.lock.Lock` object can be called and used as a context manager.
+The following code:
+
+.. code-block:: python
+
+   lock.acquire()
+   time.sleep(10)
+   lock.release()
+
+Can be re-written more safely, and conveinently, as:
+
+.. code-block:: python
+
+   with lock():
+       time.sleep(10)
+
+This ensures the releasing in the lock in the case of an unexpected exception.
+
+
 Teardown
 --------
 

src/lynk/lock.py

@@ -93,28 +93,32 @@ def _stop_refresher(self):
 
 
 class LockFactory(object):
-    """Class for constructing locks."""
+    """Class for creating locks.
+
+    A ``LockFactory`` represents the logical binding beteween an agent that
+    can interact with locks, and a backend table where the locks are stored.
+    This relationship is defined by the ``table_name`` and ``host_identifier``
+    parameters outlined below.
+
+    :type table_name: str
+    :param table_name: Name of the table in the backend.
+
+    :type host_identifier: str
+    :param host_identifier: A unique identifier for a host. A host is just
+        an unused field in the database. It is for debugging and nothing
+        more so any value can be used that has meaning to the developer.
+        By default hostname is used.
+
+    :type backend_bridge_factory: Anything with a create method or None.
+    :param backend_bridge_factory: A factory that creates our backend and
+        its associated bridge class to be injected into our lock. Usually
+        these need to be created by a shared factory class because they
+        have shared dependencies. If None is provided the default is a
+        :class:`lynk.backends.dynamodb.DynamoDBBackendBridgeFactory` which
+        will create locks bound to a DynamoDB Table.
+    """
     def __init__(self, table_name, host_identifier=None,
                  backend_bridge_factory=None):
-        """Initialize a new LockFactory.
-
-        :type table_name: str
-        :param table_name: Name of the table in the backend.
-
-        :type host_identifier: str
-        :param host_identifier: A unique identifier for a host. A host is just
-            an unused field in the database. It is for debugging and nothing
-            more so any value can be used that has meaning to the developer.
-            By default hostname is used.
-
-        :type backend_bridge_factory: Anything with a create method or None.
-        :param backend_bridge_factory: A factory that creates our backend and
-            its associated bridge class to be injected into our lock. Usually
-            these need to be created by a shared factory class because they
-            have shared dependencies. If None is provided the default is a
-            :class:`lynk.backends.dynamodb.DynamoDBBackendBridgeFactory` which
-            will create locks bound to a DynamoDB Table.
-        """
         self._table_name = table_name
         if host_identifier is None:
             host_identifier = socket.gethostname()