Started on time delay estimator.

Basic function structure, functions to calculate area between curves in a discrete fashion.
Delta estimator area method working.

More parameters for the delta estimator.
Some functions moved from combinefunction to general util because they're useful in other places too.
Launcher passes parameters to the delta estimator from the paramfile.
Delta estimator area method uses a single function to do the work, with some helpers. Due to different types of return from the gaussian and baseline estimators it takes a void pointer and the type of estimate, and it will change the calculation based on that. This stops code duplication.
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.
Progress on pmf estimator. Underlying logic working reasonably well.

Various fixes to the launcher and combinefunctions functions to work correctly with the per-stream delay system.
pmf estimator almost working. Need to work out how best to get values of the pmf when the combined function does not have a delay for all points in the interval. Try using more subintervals.
Delta estimators use parameters from paramfile.

All variables used by the delta estimator available as parameters in the file.
Start and interval time for generation and estimation now separate. Beware of bugs - not sure if all the places where the same values were used. All mentions in the estimators have been replaced, at least.y
Fixed delta estimation with pmf method.

Fixed issues caused by various math functions which were causing the pmf estimator to perform sub-optimally.
Generator no longer exceeds maximum time.
pmf estimator now uses cumulative pmf of both streams.
pmf summing no longer returns -nan if lambda is zero.
Minor fix to array interval sum, removed old functions.
Merge branch 'delay' into develop

Conflicts:
	code/ChangeLog
	code/data/params.txt
	code/src/combinefunction.c
	code/src/combinefunction.h
	code/src/estimator_gaussian.c
	code/src/generator.c
	code/src/launcher.c
	code/tests/check_combinefunction.c

Mostly minor conflicts to do with new functions in both branches.