Total focusing method

The total focusing method(TFM) using full matrix capture(FMC).

A simple implementation of the total focusing method is provided. It can scale over many cpu cores by replacing the for loop with a parfor loop and it has been generalised to be used with different kinds of complex geometries by modification of the image_domain function.
An example is provided where a 5 Mhz transducer has been used in water scanning for 6 copper wires.
The tfm function has two parameters, the fmc struct containing the FMC dataset and a domain struct containing all precalculated time delays.
The appended image_domain function models the specimen as homogeneous. It calculates all euclidean distances using the Matlab function pdist2 and saves it as matrix Rx. See pdist2 documentation for the structure of the matrix. Rx is then recalculated into the number of sampled samples to each pixel, i.e the indices of the A-scan vectors.