beremiz

file isExecutable
fix license notices in source files and license files under GPLv2+

Previously a lot of files were referenced to GNU Public License 2.1,
which never existed.
All copyright attributions are kept the same.
<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>