Changes

Note that a lot of time can be spent on improving the isolated target function code, after implementation. Troels did this for relaxation dispersion in relax, allowing relax to likely be the fastest implementation in the field for this analysis. This requires a lot of numerical tricks to take advantage of the BLAS and LAPACK routines found in the Python numpy package, converting the target functions to operate on matrices as much as possible. Speed comparisons are difficult, as the optimisation in relax is far more precise than any of the other software (precision and quality is often dropped to speed up the software). But I have the source code for many of the dispersion analysis softwares, or I directly asked the developers, and I think that only relax uses these routines. Note that the use of BLAS and LAPACK routines has orders of magnitude greater impact on software optimisation speed than the choice of programming language (Python vs. C), but that the target functions in relax can later be converted from Python to C for additional, though less impressive, speed ups.