Major changes to support multiple distfiles in templates.

Each template now needs to use $distfiles that accepts the full
URL to download the distfile and old $extract_sufx is now merged
on it, but this must be separated by the '@' character. Example:

distfiles="http://www.foo.org/blah-6.2@.tar.gz
http://www.foo.org/blob-1.0@.tar.bz2"

If distfiles contains multiple files defined, $wrksrc is now
mandatory.

--HG--
extra : convert_revision : 1c3fa35f148af8323ce3cbcf5732104960de6bc4

templates/perl-XML-Parser.tmpl

@@ -1,9 +1,9 @@
 # Template build file for 'perl-XML-Parser'.
 pkgname=perl-XML-Parser
 version=2.36
-distfiles="XML-Parser-$version"
-extract_sufx=".tar.gz"
-url=http://cpan.perl.org/modules/by-module/XML
+wrksrc="XML-Parser-$version"
+distfiles="
+http://cpan.perl.org/modules/by-module/XML/XML-Parser-$version@.tar.gz"
 build_style=perl_module
 make_build_args="EXPATLIBPATH=$XBPS_MASTERDIR/lib
  EXPATINCPATH=$XBPS_MASTERDIR/include"