Function: define-mail-abbrev

Define NAME as a mail alias abbrev that translates to DEFINITION.
If DEFINITION contains multiple addresses, separate them with commas.

Optional argument FROM-MAILRC-FILE means that DEFINITION comes
from a mailrc file. In that case, addresses are separated with
spaces and addresses with embedded spaces are surrounded by
double-quotes.

(fn NAME DEFINITION &optional FROM-MAILRC-FILE)