https://git.beagleboard.org/docs/docs.beagleboard.io/-/merge_requests/79#note_15599

Add requirements.txt

See merge request docs/docs.beagleboard.io!79

- Remove slack link
- Add link to beagleboard forum

Signed-off-by: Ayush Singh <ayushdevel1325@gmail.com>

- Remove slack link
- Add link to beagleboard forum

Signed-off-by: Ayush Singh <ayushdevel1325@gmail.com>

- Specify language for codeblocks to fix build warnings

Signed-off-by: Ayush Singh <ayushdevel1325@gmail.com>

As a work-around, we can tag a version with conf.py set with todos off,
then re-enable them for docs.beagleboard.io.

- Also change venv name to .venv since zsh scripts to auto load venv
  assume this path by default

Signed-off-by: Ayush Singh <ayushdevel1325@gmail.com>

Fix some code, code-block, and literalinclude warnings