Make ssync_receiver drop conn on exc

Before, the ssync receiver wouldn't hang up the connection with all
errors. Now it will. Hanging up early will ensure the remote end gets
a "broken pipe" type error right away instead of it possible sending
more data for quite some time before finally reading the error.

Change-Id: I2d3d55baaf10f99e7edce7843a7106875752020a
Force catch_errors into pipeline

This commit adds a hook for WSGI applications
(e.g. proxy.server.Application) to modify their WSGI pipelines. This
is currently used by the proxy server to ensure that catch_errors is
present; if it is missing, it is inserted as the first middleware in
the pipeline.

This lets us write new, mandatory middlewares for Swift without
breaking existing deployments on upgrade.

Change-Id: Ibed0f2edb6f80c25be182b3d4544e6a67c5050ad
Fix obj versioning w/non-ASCII container name

If you create a container with a non-ASCII name, and then make another
container with X-Versions-Location: first-cøntåîner, *and* you're
serializing stuff in memcache as json (the default), when the proxy
tries to make a versioned object, it will crash.

The fix is to make sure that get_container_info() always returns strs,
not unicodes.

The long-term fix would be to get rid of simplejson entirely, as its
decoder can't make up its mind whether JSON strings should be Python
strs or unicodes, and that makes it really really easy to write bugs
like this.

Change-Id: Ib20ea5fb884484a4246d7a21a9f1e2ffd82eb04f
change the last-modified header value with valid one

the Last-Modified header in Response didn't have a suitable
value - an integer part of object's timestamp.
This leads that the the if-[un]modified-since header with the
value from last-modified is always earlier than timestamp
and results the content is always newer than value of these
conditional headers.
Patched code returns math.ceil() of object's timestamp
in Last-Modified header so the later conditional header works
correctly

Closes-Bug: #1248818
Change-Id: I1ece7d008551bf989da74d23f0ed6307c45c5436
Merge "Make ssync_receiver drop conn on exc"
Merge "change the last-modified header value with valid one"
Merge "Force catch_errors into pipeline"