add support for virtuals and configs
In this release:
- add support for creating virtual and config assets. The method for creating assets remains backwards compatible: a boolean is also still supported. New values should be: 'sensor', 'actuator', 'config' or 'virtual'.
- deleteAsset has also been fixed.
- http request error handling has been improved.
the package can be found on pypy: https://pypi.python.org/pypi/att_iot_gateway/0.5.2