Blog post for the new scala installation support (sourcelevel toggle)

To provide more info on current developments.
As the current nightly stands, changing the container does not move the source level flag (but since changing the contents of the container changes the contents of the resolved classpath, classpath checks will, if appropriate, detect a legacy 2.10 library and trigger a dialog that will suggest setting the Xsource flag). In the reverse direction, of course, setting the source level flag does change the container.

This is describing the nightly, not the currently opened PR. A document talking about the current PR would e.g. not feature the sourcelevel flag, which it replaces by a scala installations toggle.

Finally, to answer your implicit question : in the current PR, changing the classpath container does changed the desired installation, so that modifications are bidirectional.