Agsadmin

Bug Fixes
- Fixed a bug creating service proxies from JSON

New Features
- Added ability to rename a service (`<service>.rename(new_service_name)`)

New Features
- Added Python 3 support (still compatible with Python 2, one code base across both versions of Python will be the plan for the foreseeable future)

Breaking release. API was re-organised, more closely aligning with the REST interface.

New Features
- Get/manage server directories
- Manage extensions
- Upload files
- Support for HTTP_PROXY/HTTPS_PROXY environment variables
- GeoDataServer, GlobeServer, GeometryServer and SearchServer server types
- Basic support for ArcGIS Portal *sharing* REST interface (can set sharing for items)

Fixes
- Improved how tokens are generated (should work with Portal-federated ArcGIS Servers now)

Bug Fixes
- Added missing dependency on python-dateutil

Bug Fixes
- The default local UTC delta wasn't being calculated