Added tutorials to index.rst

[jgerh]

Added links to tutorials

Description

Usage

# Add snippet demonstrating usage

Checklist

• [ ] I am familiar with the Contributing Guide.
• [ ] New or Existing tests cover these changes.
• [ ] The documentation is up to date with these changes.

[jgerh]

Added tutorials per [NeMo Curator] add links for the NeMo Curator tutorials to the NeMo Framework User Guide https://gitlab-master.nvidia.com/nemo-framework-tme/documentation/-/issues/28