OAK-1174: Inconsistent handling of invalid names/paths

The spec allows whitespace in names, so the parser shouldn't balk at them.
Instead we guard against them in the NameValidator during writes.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1582804 13f79535-47bb-0310-9956-ffa450edef68