This change defines a __ne__ for inequality checking, which is

necessary under Python 2.x (and the reason for some failed diffing that

was occurring). This just checks the inverse of __eq__.
It also fixes up most of the checks to ignore ordering in

OrderedDicts and most lists, so that two signatures can remain the

same even if, say, the order of fields changed.
Unit tests were added to ensure that all equality checks perform as

they're supposed to.

Unit tests pass.