[dovecot/core] 5c449a: notify-status: Remove first_unseen_seq field

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/dovecot/core
  Commit: 5c449ac9f4b353cb75b1a27f0fc96da3940829b8
      https://github.com/dovecot/core/commit/5c449ac9f4b353cb75b1a27f0fc96da3940829b8
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2017-09-18 (Mon, 18 Sep 2017)

  Changed paths:
    M src/plugins/notify-status/notify-status-plugin.c

  Log Message:
  -----------
  notify-status: Remove first_unseen_seq field

The sequence number keeps changing, so it's very unlikely to be useful.
It's also not always as efficiently available as the other fields, so
better to avoid having it.