Large-scale refactor and re-org of internal runtimes code

A full refactor of runtimes.ui and part of runtimes.core. Adds tracing,
headers, cleans up api, removes deprecated code where possible, moves
classes into private packages, makes use of new foundation.ui plugin,
and more.

A severe refactoring of runtimes, because it needs it

Bumping version to 3.0 because of large structural changes and new apis

Renamed a package, added copyright headers to most files

Lots more code cleanup, headers, NLS, string extraction, etc etc etc

Runtimes version update missed one line in the test feature