Changed solve_odes.cpp, find_clusters.cpp, and find_moments so that they a) write to file as the data is created, as opposed to doing it at the end. Also, changed them so that they take a string dir as an argument, which is the subdirectory they dump their results into. This is an optional argument, see main_moments for details. If no argument is given, they dump to the working directory. Note, the subdirectory has to exist before adding them -- the code doesn't make a directory at runtime -- doing this in c++ isn't trivial, and I wasn't bothered figuring it out