Fixes #387 - added gas facility damage analysis documentation and example notebook

[navarroc]

• Added gas facility damage analysis documentation page
• Added example notebook

[navarroc]

This needs to be tested with https://github.com/IN-CORE/pyincore/pull/574

[navarroc]

Just asking, it doesn't need to update _toc, right?

You are correct, let me fix that!

[navarroc]

Just asking, it doesn't need to update _toc, right?

You are correct, let me fix that!

fixed!