Adding the new Failures page.

Author: aezell

docs/source/failures.rst

@@ -0,0 +1,17 @@
+Failures
+===============
+
+Pyres provides a ``BaseBackend`` for handling failed jobs. You can subclass
+this backend to store failed jobs in any system you like.
+
+Currently, the only provided backend is a ``RedisBackend`` which will store
+your failed jobs into a special *failed* queue for later processing or reenqueueing.
+
+Here's a simple example::
+
+	>>> from pyres import failure
+	>>> from pyres.job import Job
+	>>> from pyres import ResQ
+	>>> r = Resq()
+	>>> job = Job.reserve('basic',r)
+	>>> job.fail("problem")