creating the create_experiment script

[arik-shurygin]

this creates some useful utility functions for validating and creating experiments and translates the experiment_creator to this new utils functions.

[arik-shurygin]

merging this myself because these scripts are basically carbon copies of the ones found in src/mechanistic_model back in DynODE which have already been reviewed. I know this is not amazing practice but for the first couple of commits I will be expediting them to make this repo useable.