added --nonet option fixing #112803 by adding --nonet when calling

* xmllint.c doc/xmllint.xml: added --nonet option
* doc/Makefile.am: fixing #112803 by adding --nonet when calling
  xsltproc or xmllint
* doc/xmllint.xml doc/xmllint.1: also added --schema doc and
  rebuilt
* HTMLparser.c: cleaned up the HTML parser context build when
  using an URL
Daniel
diff --git a/doc/xmllint.1 b/doc/xmllint.1
index 7b06def..362ef73 100644
--- a/doc/xmllint.1
+++ b/doc/xmllint.1
@@ -31,7 +31,8 @@
         | \fB--noblanks\fR | \fB--format\fR | \fB--testIO\fR | \fB--encode \fIencoding\fR\fR
         | \fB--catalogs\fR | \fB--nocatalogs\fR | \fB--auto\fR | \fB--xinclude\fR
         | \fB--loaddtd\fR | \fB--dtdattr\fR | \fB--dropdtd\fR | \fB--stream\fR
-        | \fB--chkregister\fR | \fB--relaxng\fR] [\fBxmlfile\fR]
+        | \fB--chkregister\fR | \fB--relaxng\fR | \fB--schema\fR | \fB--nonet\fR]
+        [\fBxmlfile\fR]
 .fi
 
 .SH "INTRODUCTION"
@@ -188,6 +189,14 @@
 \fB--relaxng\fR \fIschema\fR
 Use RelaxNG file named \fIschema\fR for validation.
 
+.TP
+\fB--schema\fR \fIschema\fR
+Use a W3C XML Schema file named \fIschema\fR for validation.
+
+.TP
+\fB--nonet\fR
+Do not use the Internet to fetch DTD's or entities.
+
 .SH "SHELL"
 
 .PP