Add support for 'named address' format

Overview

Currently, we support parsing bare email addresses. We want to add support for parsing '"John Smith" john.smith@foo.com' style addresses as well.

Additional BNF:

   (?<address>         (?&mailbox) | (?&group))
   (?<mailbox>         (?&name_addr) | (?&addr_spec))
   (?<name_addr>       (?&display_name)? (?&angle_addr))
   (?<angle_addr>      (?&CFWS)? < (?&addr_spec) > (?&CFWS)?)
   (?<group>           (?&display_name) : (?:(?&mailbox_list) | (?&CFWS))? ;
                                          (?&CFWS)?)
   (?<display_name>    (?&phrase))
   (?<mailbox_list>    (?&mailbox) (?: , (?&mailbox))*)

No files or tests are named. Start by locating the current entry point that parses bare email addresses and its existing tests, then trace how the supplied BNF maps to the parser. Done means accepting quoted display names with angle-bracket addresses, while preserving bare-address parsing.