[Cs-studio-core] Branch 4.0.x

Hi:

I've started a branch 4.0.x off master as discussed in today's
collaboration meeting.

With minor plugin fiddling, the 'Basic EPICS' product starts up.
The Data Browser "Editor" can now be in what used to be a "View" location,
like in the tab folder shared with a "Navigator" as in the attached
screenshot. You can also "detach" anything.
The Eclipse 4 "Quick Access" text field in the toolbar automagically lists
preferences, online help, commands related to the data browser when simply
typing "data".

There's still a lot to do to make it really work.

Thanks,
Kay