441109 Setting the osgi.os, osgi.ws and osgi.arch of the running
platform

The osgi.os, osgi.ws and osgi.arch of the environment where tycho gets
executed are set as project properties, during project setup.
The properties are named: "tycho.env.osgi.ws", "tycho.env.osgi.os" and
"tycho.env.osgi.arch".
Adding a md file for Tycho Properties

Change-Id: I3a00944a162a39121ceb8c0fc93b372ea85652e0
Signed-off-by: Martin Schreiber <m.schreiber@bachmann.info>