Fix problem: errors during keyboard-macro execution were leaving the

Fix problem: errors during keyboard-macro execution were leaving the
editor in the command reader that was spawned to execute the keyboard
macro, rather than returning to the reader that was in control when
the keyboard-macro execution was initiated.

Some of the keyboard-macro state was being mismanaged by unnecessary
calls to KEYBOARD-MACRO-DISABLE.  This was exacerbated because
KEYBOARD-MACRO-DISABLE was setting *KEYBOARD-MACRO-EXECUTING?* to #F
when it should have been left alone.