added LANL morphology function to model_parameters.py

[bking-astro]

There were function missing from model_parameters.py for all 4 LANL model morphologies.

[bfhealy]

@bking-astro Looks like we ended up committing to a branch in the main NMMA repo rather than your fork of the repo. To fix this, could you please:

• run git remote -v from your nmma directory
• Reorganize your remotes for NMMA such that origin points to your fork and upstream points to this repo (using git remote rm <name> and git remote add <name> <https link>
• Run git pull upstream main and then git push origin main to update your forked repo
• Reopen this PR from a branch in your forked repo

I'm happy to jump on zoom again to help implement this if you're available.

[bfhealy]

See #297