Squashed commit of the following:

commit 1a17a737
Author: David Hammer <dhammer@mailbox.org>
Date:   Wed Jun 28 14:27:53 2023 +0200

    Describe arbiter kernel API

commit 44abfdb9
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Jun 27 14:16:57 2023 +0200

    Reorder correct / preview / reshape

commit cb902408
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Jun 27 11:13:06 2023 +0200

    Start documenting correction addons

commit 81d95bfb
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Jun 27 10:36:18 2023 +0200

    Move preview generation before addons to avoid interference

commit 60024124
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Apr 14 12:52:20 2023 +0200

    Add generic arbiter kernels: reduce-threshold and boolean

commit dc2e5e5f
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 31 12:54:59 2023 +0200

    Add post-reshape hook, a few docstrings

commit ab9ebc69
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 31 09:48:47 2023 +0200

    Moving frame selection arbiter kernels to entry point structure

commit 57ce4b61
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Mar 21 15:34:10 2023 +0100

    Hotfix from SPB: always nd.array the mask (can be VECTOR_BOOL)

commit c15bbc65
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Mar 20 19:26:22 2023 +0100

    Add rough peakfinder9 implementation

commit 8e51b499
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Mar 20 19:25:44 2023 +0100

    Fix usage of _enabled_addons, allow time for init

commit 8ebc1ff8
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Mar 20 19:25:25 2023 +0100

    Move grid computation to utils

commit 4b550e35
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Mar 20 15:42:22 2023 +0100

    Fix pep8 warnings for setup.py

commit 9d04d20e
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 17 15:23:06 2023 +0100

    (Ab)use entry point extras to specify detectors

    TODO: add boilerplate to remaining detectors.  For now, AGIPD will have both
    IntetgratedIntensityAddon and RandomFramesAddon whereas DSSC only has RandomFramesAddon.

commit e0a8c905
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 17 13:51:28 2023 +0100

    Provide correction device plugins as entry points

commit a2f7534f
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 17 11:50:46 2023 +0100

    Fix device schema injection, add reconfigure hook, add random plugin

commit 90a1270f
Merge: 14f0b611 ff952c76
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Mar 17 09:34:03 2023 +0100

    Merge branch 'frame-selection' of ssh://git.xfel.eu:10022/calibration/calng into frame-selection

commit 14f0b611
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Feb 17 14:59:12 2023 +0100

    Make sure the mask is boolean

commit 7911e10a
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Feb 14 15:23:52 2023 +0100

    Prototype configurable frame selection arbiter

commit 4f78506f
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Feb 13 19:42:00 2023 +0100

    Add sketch of correction device addon structure

commit ff952c76
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri Feb 17 14:59:12 2023 +0100

    Make sure the mask is boolean

commit c3d2d437
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue Feb 14 15:23:52 2023 +0100

    Prototype configurable frame selection arbiter

commit ba6eaa9f
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon Feb 13 19:42:00 2023 +0100

    Add sketch of correction device addon structure