Make statsd sample rate behave better.

As Dieter pointed out in bug 1090495
(https://bugs.launchpad.net/swift/+bug/1090495), the volume of metrics
can vary wildly between StatsD metrics.

This patch implements a partial solution by reducing the sample_rate
used for known high-volume metrics (operational experience will need to
inform this over time) and introducing a new tunable,
log_statsd_sample_rate_factor which is multiplied by the sample_rate for
every statsd stat.  This tunable can be used to reduce StatsD traffic
proportionally for all metrics and is intended to replace
log_statsd_default_sample_rate, which is left alone for
backward-compatibility, should anyone be using it.

This patch also includes a drive-by fix for log_udp_port which wasn't
being converted to an int (I didn't verify that actually causes trouble
in SysLogHandler(), but it's definitely an improvement regardles).

Change-Id: Id404636e3629f6431cf1c4e64a143959750a3c23
Use a doubled proxy-logging instead of each middleware handling it
differently (if at all)

Adding a swift.source to wsgi pre_auth funcs and all middleware that makes
subrequests to proxy server.

NOTE: This change will result in a change in the number of proxy logs made for
staticweb, formpost, tempurl, and any other middleware that performs sub
requests (including swauth and SOS).

Please see docs for details.

DocImpact

Change-Id: I80cf2806add1c3d34054147e2515944be340455b
Add generated keystone documentation to misc.rst.

- Change a bit the formatting of the documention as well.
- Fix WARNING: Title underline too short. in misc.rst.

Change-Id: I2f4e36bcb5e01e984f0af0152bc5b3b9f7e942ce
Replaces Copyright statements for LLC with Foundation, removes date.

	Replaced GA code for cross-domain tracking.

Patchset addresses reviewer's comments
and follows new guidance from Foundation:
http://wiki.openstack.org/Documentation/Copyright

Adds current year to each Sphinx-built page.

Addresses only the docs copyright attribution, not code files.

Change-Id: Ib90fd1c92c8fafce2db821bc2b17cef1377cfc1e
Merge "Use a doubled proxy-logging instead of each middleware handling it differently (if at all)"
Merge "Replaces Copyright statements for LLC with Foundation, removes date."
Merge "Add generated keystone documentation to misc.rst."
Fix spelling mistakes

git ls-files | misspellings -f -
Source: https://github.com/lyda/misspell-check

Change-Id: I4132e6a276e44e2a8985238358533d315ee8d9c4
log message in exception level when path encoding errors happen.

Original code is kind of except-pass. This will ignore the error
occurs in process of encoding path. And if such error happened
without any information in logs, developer have to debug in a
long distance from error stack. That's wasting time, so there
should be a logging message here.

Fixes: bug #1123048
Change-Id: I7941b524e936241fb8d62fad5ad90de3daffe5e7
Merge "Make statsd sample rate behave better."
fix large objects with unicode

Change-Id: I2a088e6cfe354d18cb2107a42bc626c2e7822e42
Merge "log message in exception level when path encoding errors happen."
Merge "fix large objects with unicode"