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/unzip.tmpl

@@ -3,9 +3,8 @@ pkgname=unzip
 version=5.52
 wrksrc=$pkgname-$version
 patch_files=$pkgname-fix-unzipsfx.diff
-distfiles=unzip552
-extract_sufx=".tgz"
-url=ftp://ftp.info-zip.org/pub/infozip/src/
+distfiles="
+ftp://ftp.info-zip.org/pub/infozip/src/unzip552@.tgz"
 build_style=gnu_makefile
 make_cmd="$XBPS_MASTERDIR/bin/gmake"
 CFLAGS="-I. -DUNIX -Dunix -DUSE_UNSHRINK"