Syntax:  NEW KEY user_key_name lse_command help_topic remark legend
              tpu_command

  Binds an LSE command to a key.

  In most cases, you can bind commands to control keys, to numeric
  keypad keys, and to the arrow keys on all keyboards.  You may also
  bind a command to the sequence of a meta key followed by any keyboard
  key.

  The effect of a key can vary with the editing context.  The NEW KEY
  command provides definitions for keys that are used in the user
  buffers.

  The name of the special keys to be defined may be entered in keyword
  format or may be entered literally with the use of the GOLD-CTRL/V
  key.  (see the Parameter Glossary for details).

  If you change the definition of a key that was previously defined,
  LSE does not save the previous definition.

  In this example, the key sequence ctrl/B issues a TOP command:

                   LSE>  NEW KEY CTRL/B TOP

  In this example, the key sequence ctrl/B issues a BOTTOM command.
  The help topic (Bottom), remark, and legend that appear in SHOW KEY
  MAP is "BOT":

                   LSE>  NEW KEY GOLD-CTRL/B BOTTOM Bottom "My position in the bottom" BOT

  In this example, F7 is bound to the LSE command GOTO SOURCE through
  its TPU procedure name:

                  LSE>  NEW KEY F7 "" "" "" "" LSE_GOTO_SOURCE

  In this example, NEXT_SCREEN or E6 is bound to the user procedure,
  WC_NEXT_SCREEN (WC_ is an enabled grammar prefix):

                  LSE>  NEW KEY NEXT_SCREEN "" "" "" "" WC_NEXT_SCREEN

  In this example, ENTER is bound to the LSE standard key binding for
  RETURN:

                  LSE>  NEW KEY ENTER "" "" "" "" lse$key_return