Remove unused File 3 stuff from wmp format docs
Remove unused File 3 stuff from wmp format docs

paulromano/openmc,mit-crpg/openmc,walshjon/openmc,amandalund/openmc,amandalund/openmc,johnnyliu27/openmc,shikhar413/openmc,johnnyliu27/openmc,johnnyliu27/openmc,paulromano/openmc,wbinventor/openmc,walshjon/openmc,wbinventor/openmc,mit-crpg/openmc,shikhar413/openmc,mit-crpg/openmc,smharper/openmc,liangjg/openmc,walshjon/openmc,shikhar413/openmc,shikhar413/openmc,johnnyliu27/openmc,amandalund/openmc,wbinventor/openmc,walshjon/openmc,smharper/openmc,paulromano/openmc,smharper/openmc,paulromano/openmc,liangjg/openmc,amandalund/openmc,wbinventor/openmc,smharper/openmc,mit-crpg/openmc,liangjg/openmc,liangjg/openmc