Tweaks in IS after release candidate review comments from Norway:

* Added reference to affected objects in <operatingRule>
* Extending standard base type tElementWithIDAndName for impairmentSection
* Renamed @ref to @areaRef in impairmentSection
* Changed type of @absDir in impairmentSection/additionalRunningTime from up/down to raising/falling

git-svn-id: https://svn.railml.org/railML2/branches/railML2.5-RC-infrastructure-review@1269 997d4637-a740-4bf4-9a76-81fddc049f28