EmailReminder plugin to send reminders about various things

EmailReminder plugin to send reminders about various things

* Needs some cleanup and testing
* Email templates need work
* More documentation

Squashed commit of the following:

commit 1c7b418dad5ec1b7713d61b6a42d6d7a394d500f
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 17 02:17:31 2011 -0700

    * Set the reminder interval correctly

commit ae0ded8cf95210f54b4cd58dac0eeeedf2d99c67
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 17 02:15:01 2011 -0700

    Send email reminders for invitations

commit 1b596d08f5dbe765a16fbdfbd21e2ad68e8b0058
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 16 23:53:48 2011 -0700

    Handle multiple confirmation types

commit 25d83351d878f39498cd6a14fddde27f1afef2ca
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 16 18:04:57 2011 -0700

    Actually send reminders and record a record of doing so

commit 9ffc2dbee15cacc7e7f9feab492185ee9964a17e
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 16 14:20:16 2011 -0700

    Make the queue handling actually work

commit 2a6ce3c17c045bdb0a3ddf36f2c290c9c48eb003
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 16 13:27:56 2011 -0700

    Fix syntax errors

commit 054b54847dfadc490aa7d7dff12d473af31c99bb
Author: Zach Copley <zach@status.net>
Date:   Thu Jun 16 00:36:37 2011 -0700

    Registration reminders should work now, but code is untested

commit b44117017b64635aae340c260167cf1efab9b2ae
Merge: 9d1441d f74de88
Author: Zach Copley <zach@status.net>
Date:   Tue Jun 14 09:43:19 2011 -0700

    Merge branch 'email-reminder' of gitorious.org:~zcopley/statusnet/zcopleys-clone into email-reminder

    * 'email-reminder' of gitorious.org:~zcopley/statusnet/zcopleys-clone:
      Stubby EmailReminderPlugin and data class
      Remove bogus data class

    Conflicts:
    	plugins/EmailReminder/EmailReminderPlugin.php
    	plugins/EmailReminder/classes/Email_reminder.php

commit 9d1441d7366df57e38cdfaf96e006f7d2f29d889
Author: Zach Copley <zach@status.net>
Date:   Tue Jun 14 09:23:23 2011 -0700

    Most of the other classes needed to send email reminders

commit 4e9bb11dbb23556bf5c1847e7a127084b5cc217c
Author: Zach Copley <zach@status.net>
Date:   Mon Jun 13 12:10:55 2011 -0700

    size -> length

commit a9ea80ef8abae1e64d5713091baedd931b7184e2
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 10 16:38:06 2011 -0400

    Stubby EmailReminderPlugin and data class

commit 5d893f982209b245cb9113a59e49721dd6e191b6
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 10 14:01:48 2011 -0400

    Remove bogus data class

commit f74de8841a98add73536fd8a4d3cee76035b491c
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 10 16:38:06 2011 -0400

    Stubby EmailReminderPlugin and data class

commit 5b14370918233e5112a95da94567c4ed83429bc9
Author: Zach Copley <zach@status.net>
Date:   Fri Jun 10 14:01:48 2011 -0400

    Remove bogus data class