Changing data/parameters between consecutive runs about pysrurgs

[sohrabtowfighi]

I was changing the values in my input csv file between consecutive runs, and I was surprised that the printed output didn't change at all. I assume that pySRURGS is not supposed to be used that way, so it might be useful to return an error message or a warning in that case.

pySRURGS does not re-evaluate the models which are already saved in the sqlite database. I'm not sure it is necessary to check for this either, because it does not seem realistic that the data changes between runs.

Between consecutive runs with the same input file, I reduced max_num_fit_params from 3 to 2, resulting in the following error:

KeyError: 'p2'

I think I can fix this one.

[sohrabtowfighi]

I think the second issue is fixed but I inadverdently removed all memoization. Will close this issue once I fix that later today.