bugfix: find default_key in sign
fix import of OrderedDict
prune unused exceptions imports for Python 3
WIP fixing serveral Python 3 tests for #16
more tests for #16.  all now pass except one
py2.6 support for testing
more py2.6 fixes
Merge remote-tracking branch 'ttanner/fix/ordered2.6' into develop
Merge remote-tracking branch 'ttanner/fix/default_key' into develop
Merge remote-tracking branch 'zigg/fix/py3k-tests' into develop
Merge branch 'release/1.2.6'
Merge branch 'master' into dirty_encoding_ignore