new spec.ui.swt plugin

bug 418309: [Spec] Generate a document with Scout GUI Model Properties
dynamically at runtime as reference documentation or specification 
https://bugs.eclipse.org/bugs/show_bug.cgi?id=418309
Change-Id: I5d48b4662fe575c91ff6726f18352ab467f7dbb8
Signed-off-by: Adrian Sacchi <adrian.sacchi@bsiag.com>