SVGHMI: allow designating widget's sub-elements as main element child rather than descendant. Names staring with "/" in yslt call to labels() only match direct widget childs.
<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>