Fixing several instances of the same bug. When a namespace is unbound the URI in  the NamespaceContext should be stored as null instead of the empty string.
Fixing several instances of the same bug. When a namespace is unbound the URI in 
the NamespaceContext should be stored as null instead of the empty string.


git-svn-id: 21df804813e9d3638e43477f308dd0be51e5f30f@498397 13f79535-47bb-0310-9956-ffa450edef68

ronsigal/xerces,RackerWilliams/xercesj,ronsigal/xerces,RackerWilliams/xercesj,jimma/xerces,RackerWilliams/xercesj,ronsigal/xerces,jimma/xerces,jimma/xerces