[Documentation]: Posting credentials states enabled is defaulted to true, but fails during POST

[mttradebyte]

As specified here https://lyft.github.io/confidant/api.html#post--v1-credentials, it claims that enabled defaults to true. When attempting to POST credentials, confidant posts an error stating that it must not be None, suggesting that it is not defaulted at all.

    raise ValueError("Attribute '{0}' cannot be None".format(attr.attr_name))
ValueError: Attribute 'enabled' cannot be None