Updated requests to something more modern.
Merge pull request #1443 from toastdriven/cloudsearch-requests-upgrade

Updated requests to something more modern.
Add redshift to setup.py/docs index
Added underlying DynamoDB v2 support.
Merge branch 'ddb2' into develop

* ddb2:
  Added underlying DynamoDB v2 support.
Bump version to 2.9.0
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
  ...
Merge branch 'release-2.9.0' into develop

* release-2.9.0:
  Bump version to 2.9.0
Add dev prefix back to version in dev branch
Bumped the version in README.
Added back get_upload_id().
Merge pull request #1450 from reinhillmann/manifestchanges

Added back get_upload_id().
Fixing bogus docs regarding return value of import_key_pair.
Add eu-west-1 endpoint for Redshift.
Change calling_format override in storage_uri to be gs-specific.
Fixed missing raise introduced by 57a41897493e3b11fbbe47360a9d2f1033aae87d (fixes resumable download test failures)
Add clarifying comment about using OrdinaryCallingFormat in storage_uri.
Merge pull request #1455 from jterrace/calling-format-gs-specific

Change calling_format override in storage_uri to be gs-specific.
Trying to make the docs around the count param a bit more clear.
Fix typo bug in autoscale tutorial.