Changed several files to be Python3 friendly

The print syntax has been changed to be Python3 compatible.

Change-Id: Id3fcbab390f08dcb3380cfda16d7b820b03ef683
Make swift-form-signature testable

Moved the body of bin/swift-form-signature into
swift/cli/form_signature.py, like was done with swift-ring-builder and
others. Added a couple basic tests; there's not 100% coverage, but
it's better than the 0% coverage we had before.

It's almost a straight forklift, but I changed exit() calls to return
statements.

Change-Id: Ie2f702c070da24d9cdface83b9e838e9e2965085
Make swift-form-signature output a sample form

swift-form-signature would give you the required expiration-time and
HMAC signature, but it wouldn't help you actually construct the HTML
form. To do that, you had to go look at the formpost middleware's doc
string and make up a form yourself.

For convenience, this commit makes swift-form-signature output a
sample form with the computed values filled in already; the user only
needs to fill in the Swift cluster's hostname.

Change-Id: I70d70a648b78b382dbfbe8ff918e6158a7f6a0ab
Swift configuration parameter audit

This change is the result of an audit through the config parameters
provided by swift and how/if they are addressed in the swift
documentation. The documentation being the sample config files in
the /etc directory or the documentation.

This change is only concerned with the config files in etc/ next
I will look at the documentation in the doc/ folder.

This change makes the following assumptions:
  - Unless stated otherwise, the commented out parameter in the
    sample configuration is the default for swift.

  - When the default in the code differs from that of the sample
    configuration, the default in the code is correct.

Container reconciler:
  Parameter: interval
    - code: 30
    - config: 300
  Result: config = 30

Object Expirer:
  Parameter: recon_cache_path
    - code: /var/cache/swift
    - config: Parameter missing
  Result: Add parameter

swift-dispersion-populate && swift-dispersion-report
  Parameter: auth_version
    - code: 1.0
    - config: 2.0 (due to being a confusing example of how to setup
                   version 2.0).
  Result: Added 'auth_version = 1.0' to the right section (showing
          default and make the sample configuration for auth version
          2.0 easier to understand.

swift-drive-audit:
  Parameter: log_file_pattern
    - code: /var/log/kern.*[!.][!g][!z]
    - config: /var/log/kern*
  Result: config = /var/log/kern.*[!.][!g][!z]

  NOTE: swift-drive-audit uses a parameter called device_dir which
        defaults to '/srv/node'. In all other swift binaries/services
        there is a similar parameter called devices which stores the
        same thing. This is an inconsistency which I haven't fixed
        as this could break existing swift clusters out in the wild.

Proxy Server:
  Parameter: object_chunk_size
    - code: 65536
    - config: 8192
  Result: config = 65536

  Parameter: client_chunk_size
    - code: 65536
    - config: 8192
  Result: config = 65536

  Parameter: strict_cors_mode
    - code: True
    - config: No parameter
  Result: config = True

Account and Container replicator configuration confusion:
  NOTES:
    The account and container replicators have parameters:
      - interval
      - run_pause

    Both of these are loaded into the same variable in code:
      self.interval = int(conf.get('interval') or
                          conf.get('run_pause') or 30)

    If a user sets both to different values then interval is used.
  Result: Update the configuration to make this more clear.

DocImpact
Change-Id: Iaadbb1a6284f8b3e0801bc343b29772f70f4bf6e
Remove old DLO config remenents from proxy

Config items 'rate_limit_after_segment' and
'rate_limit_segments_per_sec' are configuration items left over from
before DLO was moved from the proxy server and into it's own
middleware. This change removes the configuration options from the
proxy server.

Change-Id: Ie3d42a57cda813feed019f01db986f13cdff9c31
Merge "Make swift-form-signature testable"
Merge "Make swift-form-signature output a sample form"
Merge "Swift configuration parameter audit"
Merge "Remove old DLO config remenents from proxy"
Merge "Changed several files to be Python3 friendly"