Add accurate timestamps in proxy log

Add accurate timestamps to the proxy-logging middleware log lines for
the start and end of a request. We use 9 digits of precision since on
some systems the clock resolution can be as fine as 1 ns.

The goal is to allow for log processing that can use the more accurate
timestamps to correlate requests, computing number of requests in
flight at a given historical point in time.

Change-Id: I61e8784b1c455d629f1299207fc4fc7e4a134814
Signed-off-by: Peter Portante <peter.portante@redhat.com>
Expose bulk-operation limits in /info.

These will allow clients to perform the minimal number of requests
required to accomplish some bulk tasks. For example, a client with
many objects to delete can learn that the cluster's limit on
deletes-per-request is, say, 128, and then batch up their deletes in
groups of 128. Without this, the client has to either discover the
limit out-of-band somehow (and get notified if it changes), or do some
sort of binary search to figure out the limit.

Similar reasoning applies to the containers-per-request value.

The errors-per-request values are included so that clients may size
their requests such that everything is attempted regardless of
failure.

I split the 'bulk' entry into 'bulk_delete' and 'bulk_upload' because,
from a client's standpoint, they're separate operations. It so happens
that Swift implements both in one piece of middleware, but clients
don't care.

Bonus fix: documented a missing config setting for the bulk middleware.

Change-Id: Ic3549aef79682fd5b798145c3545c1609aa1592b
Some functional tests for dynamic large objects

Change-Id: Id9f6c7e26ed9760372d2bfc9a1ffa3f8ae3d5861
Merge "Expose bulk-operation limits in /info."
Merge "Some functional tests for dynamic large objects"
Merge "Add accurate timestamps in proxy log"