runtime/Wamp : adapt to unicode being enforced in latest crossbar API. Updated some documentation, to explain why there is unused definitions like SubscribedEvents or DoOnJoin.
<xsd:element name="Xenomai">
<xsd:complexType>
%(toolchain_gcc)s
<xsd:attribute name="XenoConfig" type="xsd:string" use="optional" default="xeno-config"/>
</xsd:complexType>
</xsd:element>