Fixed systematically loading PLC binary at startup even without -a parameter. Extended py_ext extensions instances variable description (PLCGlobalsDesc). Now contains list of variables organizd by extension, with extension name
<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>