Add py-visvis 1.12.2

Visvis is a pure Python library for visualization of 1D to 4D data in an bject
oriented way. Essentially, visvis is an object oriented layer of Python on top
of OpenGl, thereby combining the power of OpenGl with the usability of Python. A
Matlab-like interface in the form of a set of functions allows easy creation of
objects (e.g. plot(), imshow(), volshow(), surf()).

With visvis a range of different data can be visualized by simply adding world
objects to a scene (or axes). These world objects can be anything from plots
(lines with markers), to images, 3D rendered volumes, shaded meshes, or you can
program your own world object class. If required, these data can also be moved
in time.

WWW: https://github.com/almarklein/visvis

• While I'm here:
  • Fix LICENSE
  • Add LICENSE_FILE
  • Use PYNUMPY
  • Add missing USES=pyqt:5

PR: 241510
Submitted by: Rainer Hurling <rhurlin@gwdg.de>