Merge branch 'release-2.9.0'

* release-2.9.0: (158 commits)
  Bump version to 2.9.0
  Added underlying DynamoDB v2 support.
  Add redshift to setup.py/docs index
  Updated requests to something more modern.
  Only use 2 metadata service calls to get credentials
  Fix #1146: return response from custom url opener
  Fixed missing import.
  Add metadata_service_num_attempts config option
  Added cleanup for the snapshots created.
  Added support for redshift.
  Let total attempts by 1 + num_retries
  Add more diagnostics to debug logs
  Change GS calls to make_request to always convert to utf-8 bytes.
  Allow kwargs to be passed through to uplaoder
  Remove whitespace, fix long line lengths
  Improve VPC and VPN support
  Added sleeps to allow amazon time to propogate
  Added error handling for out of space during downloads
  Initial integration tests for idempotent subscribe
  Removed dead code from resumable upload handler
  ...
Updated DynamoDB v2 to incorporate retries & checksums.
Fixed the error type checking.
Merge branch 'ddbv2-retries' into develop
Added a ``connect_redshift`` function for easier access to a ``RedShiftConnection``.
Change num_retries default for resumable download handler to be 6, to be consistent w/ num_retries elsewhere in the code
Initial Support API addition.
Support docs & release notes.
Merge branch 'support-api' into develop

* support-api:
  Support docs & release notes.
  Initial Support API addition.
Bumping version to 2.9.1
Merge branch 'release-2.9.1'

* release-2.9.1:
  Bumping version to 2.9.1
  Support docs & release notes.
  Initial Support API addition.
  Change num_retries default for resumable download handler to be 6, to be consistent w/ num_retries elsewhere in the code
  Added a ``connect_redshift`` function for easier access to a ``RedShiftConnection``.
  Fixed the error type checking.
  Updated DynamoDB v2 to incorporate retries & checksums.
  Allow port override in boto config
  Fix typo bug in autoscale tutorial.
  Trying to make the docs around the count param a bit more clear.
  Add clarifying comment about using OrdinaryCallingFormat in storage_uri.
  Fixed missing raise introduced by 57a41897493e3b11fbbe47360a9d2f1033aae87d (fixes resumable download test failures)
  Change calling_format override in storage_uri to be gs-specific.
  Add eu-west-1 endpoint for Redshift.
  Fixing bogus docs regarding return value of import_key_pair.
  Added back get_upload_id().
  Bumped the version in README.
  Add dev prefix back to version in dev branch
Merge branch 'release-2.9.1' into develop

* release-2.9.1:
  Bumping version to 2.9.1
Add boto.support to setup.py
Bump version to 2.9.2
Merge branch 'hotfix-2.9.2' into develop

* hotfix-2.9.2:
  Bump version to 2.9.2
  Add boto.support to setup.py
Updated docs from the v2.9.2 release.
More documentation tweaks.
Add back dev prefix to version string
Bumped the ``APIVersion`` on the support client.