Bump to scenery 0.9.0

[skalarproduktraum]

This PR prepares sciview for the scenery 0.9.0 release. It also includes the following fixes/improvements:

• bumps pom-scijava 35.1.1 and therefore updates dependencies included there
• adjusts some Java examples for API changes in scenery 0.9.0
• improves Swinginess by doing UI stuff on the EDT
• asynchronously initialises the REPL for improved startup time