[QGIS-Developer] Visual changelog of version 3.8

[Andreas Neumann]

Hi QGIS contributors,

Sorry about the delay of the publication of the 3.8 visual changelog. 
Responsibilities had been unclear. We want to publish the final version 
of the 3.8 visual changelog on the coming Monday. If you have things to 
add, please do it until Monday.

For now I will link directly to the changelog site.

For version 3.10, the changelog is already open, so you can immediately 
start adding entries.

Thanks and greetings,

Andreas