[platform-core-dev] Changes to expression language

[Dirk Baeumer <dirk_baeumer@xxxxxxxxxx>]

The adapt expression now uses the new IAdapterManager API
hasAdapter(Object, String) and
getAdapter(Object, String). This ensures that the right class loader is
used to convert
the string representing a type into a corresponding Class. However, this
change now requires
that the adapters requested via an adapt expression must be declared in XML
using the new
org.eclipse.core.runtime.adapters extension point.

I have updated the code where necessary (based on the last nightly build).

Dirk