Correct symbol space for 'all' and 'choice'. Added 'replace' normalization

* xmlschemas.c: Correct symbol space for 'all' and 'choice'.
* xmlschemastypes.c include/xmlschemastypes.h: Added 'replace'
  normalization for 'normalizedString'.
  Added xmlSchemaWhiteSpaceReplace to the API.
4 files changed