Lists variable names and definitions used inside a function
Returns a list containing the names and definitions of variables in f, apollo_randCoeff and apollo_lcPars
apollo_varList(f, apollo_inputs)
f: A function, usually apollo_probabilitiesapollo_inputs: List grouping most common inputs. Created by function apollo_validateInputs .A list of expressions containing all definitions in f, apollo_randCoeff and apollo_probabilities
It looks for variable definitions inside f, apollo_randCoeff, and apollo_lcPars. It returns them in a list.