(py-shift-region-left, py-shift-region-right, py-indent-right,

py-outdent-left, py-mode-map): Folded all functionality into
py-shift-region-* commands.  Bound C-c C-l to py-shift-region-left and
C-c C-r to py-shift-region-right.  Removed py-indent-right and
py-indent-left.