Updated the GS classes to use new-style classes as well.
Consistent use of identity comparison (`is`/`is not`) for None
Bugfix: Removing a line that shouldn't have been brought back in during merge
Return the StepSummaryList from this call
Dyanamo Table.scan() should accept 'attributes' argument
Added support for reduced page sizes in DDB.

This allows for faster responses & from a large scan/query drowning out other requests.
Fixed an inheritance bug in mturk.
Bumped to 2.21.2!
Merge branch 'ddb-max-page-size' into develop
Fixes #1949.
Properly handle getopt long options in s3put

Fixes #1946, where `-r` was mistakenly processed as if `--region` had been
passed because of incorrectly initialized tuples.
Merge pull request #1950 from danielgtaylor/s3put-opts

Properly handle getopt long options in s3put. Fixes #1950, #1946.
Merge remote-tracking branch 'upstream/develop' into consistent-identity-comparison-none

Conflicts:
	boto/manage/server.py
Proper string parameter handling in connection.
fix typo in docstring for ssh_client.run
Merge pull request #1953 from kanzure/fix-sshclient-typo

Fix typo in docstring for SSHClient.run. Fixes #1953.
Add unit test for unicode calling format
Merge pull request #1954 from danielgtaylor/kdeldycke-string-parameter-s3

Fix unicode string parameter handling in S3Connection. Fixes #1954, #1952.
Add missing parameters to get_spot_price_history method.  Fixes #1957.
Fix string type tests.
Merge pull request #1958 from garnaat/fix-1957

Add missing parameters to get_spot_price_history method.