AYON to ftrack sync: Sync AYON changes to ftrack

[iLLiCiTiT]

Changelog Description

Synchronization of AYON changes to ftrack.

Additional review information

This PR combination of multiple other PRs.

• New service 'transmitter' in ftrack addon which listens to AYON events and handles sync to ftrack.
• Synchronization of assignees between tasks if ftrack id is filled in AYON.
• Synchronization of statuses from AYON to ftrack.
• Synchronization of attributes from AYON to ftrack.
• Simple synchronization of comment from AYON to ftrack. We don't capture removed comments in AYON (future enhancement).

Testing notes:

1. Clone repository and go to ./service_tools.
2. Run ./manage.ps1 install on windows or make install on linux/mac.
3. Run ./manage.ps1 services on windows or make services on linux/mac (You can run just transmitter instead of services).
4. Changes in AYON should propagate to ftrack and changes in ftrack should propagate to AYON.

Resolves #133

[64qam]

LGTM @MilaKudr could you please also test it?

[MilaKudr]

In many cases it works, but for some tasks/shots I get these errors during Ayon to ftrack sync:
File "C:\Users\Mila\code\ayon-ftrack\service_tools\venv\lib\site-packages\ftrack_api\session.py", line 1687, in call
raise ftrack_api.exception.ServerError(error_message)
ftrack_api.exception.ServerError: Server reported error: ParseError(No attribute 'parent_id exists for schema 'Asset'.)

[iLLiCiTiT]

In many cases it works, but for some tasks/shots I get these errors during Ayon to ftrack sync:
File "C:\Users\Mila\code\ayon-ftrack\service_tools\venv\lib\site-packages\ftrack_api\session.py", line 1687, in call
raise ftrack_api.exception.ServerError(error_message)
ftrack_api.exception.ServerError: Server reported error: ParseError(No attribute 'parent_id exists for schema 'Asset'.)

Fixed, try again.