add versioning standard to docs

Author: MarAl3

schema/cpacs_schema.xsd

@@ -36383,7 +36383,7 @@ The fuel tank volume type should also be used for the wing fuel tank</xsd:docume
                 <xsd:all>
                     <xsd:element name="cpacsVersion" type="xsd:string">
                         <xsd:annotation>
-                            <xsd:documentation>CPACS version of the dataset
+                            <xsd:documentation>CPACS version of the dataset according to the Semantic Versioning 2.0.0 standard.
                             </xsd:documentation>
                         </xsd:annotation>
                     </xsd:element>
@@ -36407,7 +36407,13 @@ The fuel tank volume type should also be used for the wing fuel tank</xsd:docume
                     </xsd:element>
                     <xsd:element name="changeLog" minOccurs="0" type="changeLogType"/>
                 </xsd:all>
-                <xsd:attribute name="version" use="required" type="xsd:string"/>
+                <xsd:attribute name="version" use="required" type="xsd:string">
+                    <xsd:annotation>
+                        <xsd:documentation>
+                            Reference to the &lt;version&gt; element in the &lt;header&gt; node, for which additional metadata is specified. The &lt;version&gt; element follows Semantic Versioning 2.0.0 standard, as does the corresponding attribute link.
+                        </xsd:documentation>
+                    </xsd:annotation>
+                </xsd:attribute>
             </xsd:extension>
         </xsd:complexContent>
     </xsd:complexType>