Mark user-manual as UTF-8

There have been several complaints against k.org's user-manual
page.  The document is generated in ISO-8859-1 by the xsltproc
toolchain (I suspect this is because released docbook.xsl we use
has xsl:output element that says the output is ISO-8859-1) but
server delivers it with "charset=UTF-8", and all h*ll breaks
loose.

This attempts to force UTF-8 on the generating end.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/Makefile

@@ -131,7 +131,7 @@ clean:
 user-manual.xml: user-manual.txt user-manual.conf
 	$(ASCIIDOC) -b docbook -d book $<
 
-XSLT = http://docbook.sourceforge.net/release/xsl/current/html/docbook.xsl
+XSLT = docbook.xsl
 XSLTOPTS = --xinclude --stringparam html.stylesheet docbook-xsl.css
 
 user-manual.html: user-manual.xml

Documentation/docbook.xsl

@@ -0,0 +1,5 @@
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+		version='1.0'>
+ <xsl:import href="http://docbook.sourceforge.net/release/xsl/current/html/docbook.xsl"/>
+ <xsl:output method="html" encoding="UTF-8" indent="no" />
+</xsl:stylesheet>