Revert "Revert "Use standalone launcher by default""
This reverts commit 91e0f7e330c9dd514c2d682974c73c8fbef33f80.
Remove old project list etc
Fix file associations
Make default scene camera position less confusing
Remove ShowStartScreen editor preference, as it no longer applies
Tweak editor startup for single project mode
Move SuppressBuildNotifications to the right position