Big-ish commit, speedups

Removed attempt at paralellizing Lagrange_deriv

Speedups all around!
After performing simple benchmarking tests, Changed parameters finders
appendings to push!. Gained significant speedup in both parallel and
serial processing.

Performed a profiling to see where all the time was going. Found all to
be in read-in time.
Switched from CSV to binary. Now serial and parallel times are
comparable for data sets of 1 million points.