MoveText allows you to move the current line using M-up / M-down (or any other bindings you choose) if a region is marked, it will move the region instead.
Using the prefix arg (C-u number or META number) will predetermine how many lines to move.
Install from MELPA (or MELPA stable)
M-x package-install move-text <RETURN>
If you want to use the default bindings, add the following to .emacs
This sets the keyboard shortcuts:
move-text-up(line or active region)
move-text-down(line or active region)