Squashed commit of the following:

commit beb32df5
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri May 13 13:25:10 2022 +0200

    Fix reconfigure bug and prevent sources from being sorted

commit a79b501a
Author: David Hammer <dhammer@mailbox.org>
Date:   Wed May 11 12:35:09 2022 +0200

    Update description of stacking patterns

commit 426d707b
Merge: 07b6c972 e1b0b8d1
Author: David Hammer <dhammer@mailbox.org>
Date:   Mon May 9 12:50:30 2022 +0200

    Merge branch 'stacking-shmem-matcher' of ssh://git.xfel.eu:10022/karaboDevices/calng into stacking-shmem-matcher

commit 07b6c972
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri May 6 14:53:31 2022 +0200

    Adding option to skip Karabo channel output

commit 02a4ccd9
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri May 6 13:27:59 2022 +0200

    Allow stacking on other axes, fix thread pool

commit b2b5aca1
Author: David Hammer <dhammer@mailbox.org>
Date:   Thu May 5 16:30:14 2022 +0200

    Allow thread pool usage

commit f8f380cc
Author: David Hammer <dhammer@mailbox.org>
Date:   Thu May 5 14:49:01 2022 +0200

    Use sources list to get source order, cache buffers

commit ef898211
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue May 3 15:49:21 2022 +0200

    Adding Philipp's proposed changes to TrainMatcher for merging

commit e1b0b8d1
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri May 6 14:53:31 2022 +0200

    Adding option to skip Karabo channel output

commit bbb7cee4
Author: David Hammer <dhammer@mailbox.org>
Date:   Fri May 6 13:27:59 2022 +0200

    Allow stacking on other axes, fix thread pool

commit b01015c4
Author: David Hammer <dhammer@mailbox.org>
Date:   Thu May 5 16:30:14 2022 +0200

    Allow thread pool usage

commit e7f96bae
Author: David Hammer <dhammer@mailbox.org>
Date:   Thu May 5 14:49:01 2022 +0200

    Use sources list to get source order, cache buffers

commit 193264ed
Author: David Hammer <dhammer@mailbox.org>
Date:   Tue May 3 15:49:21 2022 +0200

    Adding Philipp's proposed changes to TrainMatcher for merging