JupiterOne Python SDK 1.2.1

What's Changed

• updating README by @SeaBlooms in #28
• add support for 'syncMode' and 'source' request params for Sync Jobs by @SeaBlooms in #29
• add alert rule methods by @SeaBlooms in #30
• added alert rule management methods - v1.2.0 by @SeaBlooms in #31
• bump version to 1.2.0 by @SeaBlooms in #32
• Update constants.py by @SeaBlooms in #33
• README update and bump version 1.2.1 by @SeaBlooms in #34

Full Changelog: v1.1.0...v1.2.1