[492190] Stereotypes not displayed in SMV for SYSML elements

Introduced a FilteredLabelProvider for Papyrus UML elements that
retrieves their label based on the available customizations for the
given element.

Bug: 492190

Change-Id: Ifec7f17d89bcc9f9601ee959fe3db6e5a3dc61b2
Signed-off-by: Alexandra Buzila <abuzila@eclipsesource.com>
8 files changed