Release 2.1.1 - Bug fixes for Docker API and TETHYS_SRC

This patch makes the following fixes:

• tethys docker CLI API was refactored to work with the latest version of docker-py
• upgrade of the docker-py version allows the Tethys environment to resolve to Python version 3.6
• fixes to the activate and deactivate script to add the TETHYS_SRC variable to the environment when it is activated

2.1.0

• Python 3 Officially Supported
• Python 2 Support Deprecated
• 100% Unit Test Coverage
• Tethys Extensions
• Many more basemaps on MapView
• Control version of OpenLayers used by MapView
• Class-based controller support
• Partial install options in install script for Linux and Mac
• New commands to automate tethys services and app settings
• Dockerfile
• API Tokens for Users
• Documentation for SSL use in production
• Bug fixes

2.0.0: HydroShare OAuth Fixed

Fixes an issue with HydroShare OAuth backend that was introduced in 2.0.0.

2.0.1: Fix Installation (#303)

* Fixes `gen settings` command on Windows install script
* Fixes `DOSKEY tstart` command in Windows install script
* Fixes issue with `CONDA_HOME` in Linux install script when installing Docker
* Temporary fix to resolve branch in the docs on Read The Docs
* bumps version to 2.0.1