Trim whitespaces is now manual

It does not longer automatically occur on save.
Available as an atomic action (Ctrl+Shit+C) or as part of
a source code formatting (in Eclipse : Source>Format)
Redevelopment of the nit setup configuration wizard
Update parser with the latest official syntax
Reorganization of imports
Fix: bad location of the parser
Adding FFI support (C extern code)
Refactoring : outline moved outside ui/editor package
Link outline selection(tree) to the text editor(file)
Link text editor selection to the outline(tree)
Merge branch 'master' of https://github.com/nheu/Nit-Plugin-for-Eclipse into mergeNheu