* Consistenty use javax annotations.
- Unfortunately jetbrains annotations seem to be exposed transitively via core somewhere, but with the correct IDE settings, annotations can be defaulted to javax
- Cleaning up of import order in #1195
- Must be merged before #1195
* Add and apply .editorconfig from P2
- Does not rearrange entries
* Address some comments
* add back some javadoc comments
* Address final comments
Co-authored-by: NotMyFault <mc.cache@web.de>