Geoviewpoint: added zFar and zNear fields
Merge branch 'master' of https://github.com/x3dom/x3dom into GeoViewpoint_work
Merge branch 'GeoPositionInterpolator_work' of https://github.com/andreasplesch/x3dom into GeoPositionInterpolator_work

initial update
Merge branch 'GeoPositionInterpolator_work' of https://github.com/andreasplesch/x3dom into GeoPositionInterpolator_work
GeoPositionInterpolator: improved description; use hint key for linear interpolation