revamped the elfgcchack.h format to cope with gcc4 change of aliasing

* doc/apibuild.py doc/elfgcchack.xsl: revamped the elfgcchack.h
  format to cope with gcc4 change of aliasing allowed scopes, had
  to add extra informations to doc/libxml2-api.xml to separate
  the header from the c module source.
* *.c: updated all c library files to add a #define bottom_xxx
  and reimport elfgcchack.h thereafter, and a bit of cleanups.
* doc//* testapi.c: regenerated when rebuilding the API
Daniel
diff --git a/doc/APIchunk1.html b/doc/APIchunk1.html
index eb14d20..40e070e 100644
--- a/doc/APIchunk1.html
+++ b/doc/APIchunk1.html
@@ -172,6 +172,7 @@
 <a href="html/libxml-parserInternals.html#xmlParseCharRef">xmlParseCharRef</a><br />
 </dd><dt>Characters</dt><dd><a href="html/libxml-parserInternals.html#xmlParseCharRef">xmlParseCharRef</a><br />
 </dd><dt>Checka</dt><dd><a href="html/libxml-xmlschemastypes.html#xmlSchemaValidateLengthFacet">xmlSchemaValidateLengthFacet</a><br />
+<a href="html/libxml-xmlschemastypes.html#xmlSchemaValidateLengthFacetWhtsp">xmlSchemaValidateLengthFacetWhtsp</a><br />
 </dd><dt>Checks</dt><dd><a href="html/libxml-HTMLparser.html#htmlAttrAllowed">htmlAttrAllowed</a><br />
 <a href="html/libxml-HTMLparser.html#htmlElementAllowedHere">htmlElementAllowedHere</a><br />
 <a href="html/libxml-HTMLparser.html#htmlElementAllowedHereDesc">htmlElementAllowedHereDesc</a><br />