Python Sensor debug_draw

[aclegg3]

Motivation and Context

It can be useful to define custom debug drawing methods with a derived Simulator class (e.g. in Habitat-lab). This PR adds a hook to a debug_draw() function stub which is called in simulator.get_sensor_observations() and can be overridden for application specific debugging visualizations.

For example,

How Has This Been Tested

Overrode this in a Habitat-lab task and added DebugLineRender commands for an evaluation camera sensor.

Types of changes

• [ ] Docs change / refactoring / dependency upgrade
• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have completed my CLA (see CONTRIBUTING)
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.