lmtp: Ported to use lib-smtp/server. Implicitly fixes handling of multi-line replies from proxy backend. Implicitly adds support for mixing local and proxy recipients. Implicitly adds support for SMTP CHUNKING. RCPT failures are reported back to the client immediately, rather than waiting for the DATA command.

lmtp: Split off local delivery in a struct separate from the client. This mimics proxy delivery, making the implementation better structured.

lmtp: commands: Moved RCPT command handling relating to local recipients to lmtp-local.c.

lmtp: client: Moved recipient deinitialization to lmtp-local.c.

lmtp: local: Renamed client_input_data_write_local() to lmtp_local_data().

lmtp: local: Renamed client_rcpt_anvil_disconnect() to lmtp_local_rcpt_anvil_disconnect().

lmtp: Renamed struct mail_recipient to struct lmtp_recipient.

lmtp: Moved client_input_data_write_local() from commands.c to lmtp-local.c.

lmtp: Moved client_open_raw_mail() from commands.c to lmtp-local.c.

lmtp: Moved client_rcpt_fail_all() from commands.c to lmtp-local.c.

lmtp: Moved client_deliver_to_rcpts() from commands.c to lmtp-local.c.

lmtp: Moved client_deliver() from commands.c to lmtp-local.c.

lmtp: Moved rcpt_anvil_lookup_callback() from commands.c to lmtp-local.c.

lmtp: Moved cmd_rcpt_finish() from commands.c to lmtp-local.c.

lmtp: Moved client_rcpt_anvil_disconnect() from client.c to lmtp-local.c.