v0.19.0

• Add new samples and delete redundant ones
• Clean up hidden_views by making it an attribute of WorkbookItem
• Add type hints for workbook and data source revisions, data alerts, Favorites, Flows, groups, permissions, projects, flow runs, site, subscriptions, Users, webhooks
• add get_by_id method and test for schedules
• Allow null value for user quota tiers
• fix workbook.delete_extract
• add publish to pypi action
  fix xml generation for items
• Add Status, ParentProjectId and StartedAt filters for jobs endpoint
• make project_id nullable to support "Personal Space" for workbooks
• create single Credentials class
• Reassign content on user removal
• add redaction method to remove passwords when logging requests and responses, which can contain embedded credentials.
• remove support for python 3.6 (add python version enforcement in setup.py)
• Extract refreshable item IDs from job XML response
• Do not eagerly fetch content when a stream was requested
• Fix QuerySet slicing logic
• add CRUD methods for default permissions
• refactor Resource Types and add sample code