Fixed issues with API v2 post-processing

Merged base handler render_string and render methods into render method
Refactored base handlers for API v1 and v2
Fixed redirect issues for auth handlers

Merged base handler render_string and render methods into render method
Refactored base handlers for API v1 and v2
Fixed redirect issues for auth handlers

Merged base handler render_string and render methods into render method
Refactored base handlers for API v1 and v2
Fixed redirect issues for auth handlers

Fixed incorrect import of cryptography ExtensionNotFound
Fixed issues with redirect being called from thread without event loop
Fixed mistake in websocket server broadcast method
Added retry for downloading source release updates

Refactored log error to log debug in itasa.py
Fixed ProxyError requests.adapters in send when attempting API token refresh