Pennsieve

Added
- Support for Python 3!

Changed
- The `upload()` methods of `Dataset` and `Collection` objects and the
`append_files()` method of `TimeSeries` can now be passed a list of files or
separate file arguments.
- Updated documentation and documentation URLs.
- Unpinned version of the `pytz` dependency.

Fixed
- Fixed overrides of concept and streaming API hosts.

Removed
- `TimeSeries` streaming upload API.
- Deprecated `set` and `append` methods.

Added
- Support for topology endpoints

Changed
- Client now raises an exception when creating a dataset with an existing name
- Removed concurrent requests capabilities
- Improved timeout and retry handling

Fixed
- `owner_id` property on datasets and packages
- Deadlock caused by importing the client from another module

Removed
- Ledger API

Added
- Support for model templates
Changed
- Cleaned up Travis config
- Updated to use new date format

Changed
- Added a new release target which will build images on each new release that can be used to run unit tests.
- Updated concepts instance delete function to handle new response

Changed
- Updated documentation

Changed
- Resolved issue related to timed out APIs calls during file upload