WIP: Dev openglaccelerated playback#282

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nolyn wants to merge 29 commits intodevelopfrom

dev_openGLacceleratedPlayback

Commits on Oct 1, 2020

using the qt cube opengl example as a basis. modified the separate
nolyn
committed

Commits on Oct 2, 2020

made openglwidget central widget. it now renders properly on the
nolyn
committed

Commits on Oct 8, 2020

Commits on Oct 13, 2020

for opengl widget, moved update format signalling into update
nolyn
committed

Commits on Oct 14, 2020

Commits on Oct 19, 2020

Commits on Oct 25, 2020

opengl playback: increased number of triangles used for the rectangle
nolyn
committed