Port cw.Binary to io.BytesIO And add plenty of tests too!

[py3k] execfile → exec

[py3k] file → open

[py3k] six.integer_types

[py3k] basestring → six.string_types

[py3k] import CookieJar using six.moves

[py3k] import urllib2 from six.moves

[py3k] import range using six.moves

[py3k] import queue using six.moves

[py3k] import filter using six.moves

[py3k] import zip using six.moves

[py3k] import SimpleCookie using six.moves

[py3k] import HTTP client constants and exceptions using six.moves

[py3k] import URL mangling functions using six.moves

[py3k] import 'pickle' using six.moves

[pkg] Add dependency on six 1.4.0

[tests] Replace use of deprecated TestCase.assert_

[predicates] Simplify range(len()) iteration

[dataimport] Use pickle.dump instead of dumps

[web/facet] Simplify reversed/sorted calls

[web/test] Use TestCase.setUpClass instead of setUpModule

Use isinstance() instead of type comparison

Unused imports

[py3k] tuple unpacking in function args

[py3k] ur'' is gone

[py3k] octals and long

[py3k] Fix raise with embedded traceback python 3 removed the raise syntax with 2 and 3 expressions.

[py3k] print function

[py3k] except as

[py3k] backtick to repr

[hooks/syncschema] make sure CWUniqueTogetherConstraintDelOp happens before CWConstraintDelOp SQLServer refuses to index an unlimited text column, so we should drop unique_together constraints (which imply an index) before we drop size constraints. Closes #5560601.

[hooks/syncschema] only call "ALTER TABLE" once when changing a size constraint Until now we would: - remove the old size constraint from the in-memory schema - call update_rdef_column which removes the size restriction from the column's type - add the new constraint object - call update_rdef_column which adds the size restriction back This breaks on SQL Server when the column is involved in an index (e.g. as part of a multi-column unique constraint), because in the intermediate stage the column's type is "nvarchar(max)", which is not indexable. Of course we must still detect the case where a size constraint is really dropped and update the db schema accordingly. Closes #5557633.