Import the Python implementation of the Sethares dissonance measure by endolith.
Use np package for numpy instead of direct imports.

So that the usage of numpy function is clear.
Refactor the code a bit.
Fix a bug - the dissonance unison should not be computed twice.

The first value was hardcoded to 0.0, although the computed value is non-zero.
Although 1000 intervals  beginning with the unison were evaluated, the result length was 1001, since 0.0 was prepended.
Refactor the code a bit and add some comments.
Extract functions from the evaluation code.
Refactor the dissonance function code.
Compare the classic Plomp-Levelt and the proposed log-normal roughness curves.
Extract a method for generating and saving a sound.
Generate random dissonance pair tones.
Merge branch 'sethares-dissonance'