Re-organized C code templates for plc_main. Moved logging out of plc_debug. Factorized redundant _common_ticktime external declaration
<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>