epm-download: add yumdownloader support

bin/epm-download

 #!/bin/sh
 #
-# Copyright (C) 2015  Etersoft
-# Copyright (C) 2015  Vitaly Lipatov <lav@etersoft.ru>
+# Copyright (C) 2016  Etersoft
+# Copyright (C) 2016  Vitaly Lipatov <lav@etersoft.ru>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License as published by
@@ -28,6 +28,11 @@ epm_download()
 	aptcyg)
 		sudocmd apt-cyg download $pkg_filenames
 		;;
+	yum-rpm)
+		# TODO: check yum install --downloadonly --downloaddir=/tmp <package-name>
+		assure_exists yumdownloader yum-utils
+		sudo yumdownloader $pkg_filenames
+		;;
 	*)
 		fatal "Have no suitable command for $PMTYPE"
 		;;