Prototype for pmf delta estimator, combining gaussians.

Gaussian function combination now possible. Need to work out how to deal with normalisation.
Launcher now takes into account which delta estimation method is being used.
Function for initialisation of double_multi_arr structs to make code cleaner.
PMF delay estimator improved, helper functions for various things

Functions in math_util for calculating pmf sums, getting gaussian sums at many points, finding the largest absolute value in an array.
PMF delay estimator prototype has a better structure and is almost working.
Function combination modified. Should now receive an array containing n-1 value, where n is the number of functions being combined. Previously the first function had a delay as well, but this one is considered to be zero-based and therefore have no delay. Not sure if this change will stay, because it causes some issues with the generator.
Functions for initialising structs.