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/python.tmpl

@@ -1,11 +1,11 @@
 # Template build file for 'python'
 pkgname=python
 version=2.5.2
-distfiles="Python-$version"
-extract_sufx=".tar.bz2"
+wrksrc="Python-$version"
 patch_files="python-fix-build.diff python-fix-curses-module.diff 
  python-fix-bluetooth.diff python-fix-mremap.diff"
-url=http://www.python.org/ftp/python/$version
+distfiles="
+http://www.python.org/ftp/python/$version/Python-$version@.tar.bz2"
 configure_args="--with-threads --enable-shared"
 build_style=gnu_configure
 short_desc="Interpreted, interactive, object-oriented programming language"