Modified the offset size value for the on the fly gradient calculation.
Mainly modifying the constraints of what should be a valid normal for the styles, modified to a more restrictive value. This constraint could be modified again on the future.
Merge pull request #354 from aarbelaiz/volren-minor-corrections

Some minor corrections for the volume rendering component
Make MultiPart compatible with fitAll + showAll and add a fitPart function
Merge branch 'master' of https://github.com/x3dom/x3dom
detect mouse- enter/leave between multiple overlapping MultiPart nodes