added new APIs for creating reader from sources or reusing a reader with a

* xmlreader.c include/libxml/xmlreader.h: added new APIs
  for creating reader from sources or reusing a reader with
  a new source, like the xmlReadxx and xmlCtxtReadxxx
* win32/libxml2.def.src doc/libxml2-api.xml doc/apibuild.py
  doc/Makefile.am: regenerated the APIs
* doc/xml.html: applied a patch from Stefan Kost for namesapce docs
Daniel

python/libxml2class.txt

@@ -133,15 +133,7 @@ createFileParserCtxt()
 createMemoryParserCtxt()
 htmlCreateFileParserCtxt()
 htmlInitAutoClose()
-isBaseChar()
-isBlank()
-isChar()
-isCombining()
-isDigit()
-isExtender()
-isIdeographic()
 isLetter()
-isPubidChar()
 namePop()
 namePush()
 nodePop()
@@ -213,6 +205,10 @@ resetLastError()
 
 # functions from module xmlreader
 newTextReaderFilename()
+readerForDoc()
+readerForFd()
+readerForFile()
+readerForMemory()
 
 # functions from module xmlregexp
 regexpCompile()
@@ -709,6 +705,10 @@ Class xmlTextReader(xmlTextReaderCore)
     SetParserProp()
     Value()
     XmlLang()
+    readerNewDoc()
+    readerNewFd()
+    readerNewFile()
+    readerNewMemory()
 Class xmlReg()
 
     # functions from module xmlregexp