315.fre list tool

[singhd789]

Describe your changes

Adds fre list exps and fre list platforms tools, along with tests and some documentation.

fre list exps:

• combines the model yaml with "experiment", "platforms", "target" placeholder (if not done, will get undefined alias error message) to create intermediate combined file
• parses the combined file to list pp experiments available
• cleans/removes the combined yaml file

fre list platforms:

• combines the model and platforms yaml with "experiment", "platforms", "target" placeholder (if not done, will get undefined alias error message) to create intermediate combined file
• parses the combined file to list the platforms available
• cleans/removes combined yaml file

Issue ticket number and link (if applicable)

#315

Checklist before requesting a review

• I ran my code
• I tried to make my code readable
• I tried to comment my code
• I wrote a new test, if applicable
• I wrote new instructions/documentation, if applicable
• I ran pytest and inspected it's output
• I ran pylint and attempted to implement some of it's feedback

[ilaflott]

this is a solid effort but i have questions before i click an approve button

[ceblanton]

Looks great! Thanks Dana.

[ceblanton]

@ilaflott what concerns do you have about this handy list'er?

[singhd789]

I just have to add in validation real quick, just btw