Track conditions

Martin Lehmann suggested the new element trackCondition to be introduced in trackElements.

see http://www.railml.org/forum/ro/index.php?group=1&id=56

in the file: "infrastructure.xsd"

<xs:complexType name="eTrackElements">
  <xs:sequence>
    ...
    <xs:element name="trackConditions" type="rail:eTrackConditions" minOccurs="0" />
</xs:complexType>

<xs:complexType name="eTrackConditions">
  <xs:sequence>
    <xs:element name="trackCondition" type="rail:tTrackCondition" minOccurs="0" maxOccurs="unbounded" />
  </xs:sequence>
</xs:complexType>

in the file: "infrastructureTypes.xsd":

<xs:complexType name="tTrackCondition">
  <xs:complexContent>
    <xs:extension base="rail:tOrientedElement">
      <xs:attribute name="length" type="rail:tLengthM" />
      <xs:attribute name="type" type="xs:string" />
    </xs:extension>
  </xs:complexContent>
</xs:complexType>

the type attribute may have some of the following enumeration values:

• eddyCurrentBrakeProhibit
• mainSwitchOff
• emergencyBrakeBypass
• other:xxx

see #1