Add manifest file to include README.md in package

Fix HTTP body none issue

Update API endpoint URLs

Bugfix: Only use OAuth client if it's actually set

Replace 'print' statement with call to logger

Allow passing parameters of type long when an int is expected.

The test, test_parameter_type_long, added in commit cde2a133, now passes.

Add a new test, test_parameter_type_long, which demonstrates that passing parameters of type long when an int is expected, causes an exception.

ERROR: test_parameter_type_long (test.test_core.CoreTests)
...
ValueError: Bad value for parameter limit of type 'int' - 5

Production API or the Sandbox API.

Use the proper form in python-oauth2 for setting the verifier
value for use in getting the access token & secret.

Change file check from isinstance(value, file) to hasattr(value, 'read') so that file-like objects are handled.

-                if isinstance(value, file):
-                    file_object = value
-                    files.append((name, file_object.name, file_object.read()))
+                if hasattr(value, 'read'):
+                    files.append((name, value.name, value.read()))

"includes" parameter for associations, since this parameter isn't
listed in the method table.

(i.e.: oauth2.Token) and a logging.Logger

and not have to import or know about the oauth2 package.

needed especially in order to let the client pass in an oauth_callback
when calling get_signin_url.

that are read-only can opt to not import etsy.oauth and not need oauth2
installed.

setuptools extra).