Adds perceptive navigation example

[pascal-roth]

Description

STILL NEEDS TO BE TUNED

Adds a perceptive navigation example with ANYmal. The policy trains in a pillar environment with depth camera observations. The example introdcues multiple important terms for navigation, mostly taken from https://github.com/leggedrobotics/nav-suite.

This change depends on leggedrobotics/rsl_rl#114

Type of change

• New feature (non-breaking change which adds functionality)
• Documentation update

Screenshots

Checklist

• I have read and understood the contribution guidelines
• I have run the pre-commit checks with ./isaaclab.sh --format
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have updated the changelog and the corresponding version in the extension's config/extension.toml file
• I have added my name to the CONTRIBUTORS.md or my name already exists there