Simplify release notes of final versions

[manolo]

The objetive is to have simpler release-notes, so as the reader can focus on the interesting changes for the release.

• We can use collapsable panels for the long list of components, or certain sections
• Content that is repeated always in all releases should go to the readme file (contributing, reporting, etc)

[DykiSA]

Obviously it seems required since I also feel annoyed when looking for what importance thing of each releases. For example usually I did some tracking of the releases of minor version e.g. 14.x to 14.x.

I said it will be helpful because if anyone including me encountered any issues, we can use it as guidance in regards of why it is happened. Other than that, sometimes I spent time to exploring new minor releases and see if that can improve my app.