send-email: Fix Pine address book parsing

send-email: Fix Pine address book parsing

See:  http://www.washington.edu/pine/tech-notes/low-level.html

Entries with a fcc or comment field after the address weren't parsed
correctly.

Continuation lines, identified by leading spaces, were also not handled.

Distribution lists which had ( ) around a list of addresses did not have
the parenthesis removed.

Signed-off-by: Trent Piepho <tpiepho@freescale.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>