Read the region as a keyboard macro definition.
The region is interpreted as spelled-out keystrokes, e.g., "M-x abc RET".
See documentation for `edmacro-mode' for details.
Leading/trailing "C-x (" and "C-x )" in the text are allowed and ignored.
The resulting macro is installed as the "current" keyboard macro.
In Lisp, may also be called with a single STRING argument in which case
the result is returned rather than being installed as the current macro.
The result will be a string if possible, otherwise an event vector.
Second argument NEED-VECTOR means to return an event vector always. (fn START &optional END)