* Split ShardedWorkerHandlingConfig
This is so that we have a type level understanding of when it is safe to
call `get_instance(..)` (as opposed to `should_handle(..)`).
* Remove special cases in ShardedWorkerHandlingConfig.
`ShardedWorkerHandlingConfig` tried to handle the various different ways
it was possible to configure federation senders and pushers. This led to
special cases that weren't hit during testing.
To fix this the handling of the different cases is moved from there and
`generic_worker` into the worker config class. This allows us to have
the logic in one place and allows the rest of the code to ignore the
different cases.
This PR adds a new config option to the `push` section of the homeserver config, `group_unread_count_by_room`. By default Synapse will group push notifications by room (so if you have 1000 unread messages, if they lie in 55 rooms, you'll see an unread count on your phone of 55).
However, it is also useful to be able to send out the true count of unread messages if desired. If `group_unread_count_by_room` is set to `false`, then with the above example, one would see an unread count of 1000 (email anyone?).
Generally try to make this more comprehensible, and make it match the
conventions.
I've removed the documentation for all the settings which allow you to change
the names of the template files, because I can't really see why they are
useful.
The general idea here is that config examples should just have a hash and no
extraneous whitespace, both to make it easier for people who don't understand
yaml, and to make the examples stand out from the comments.
The redact_content option never worked because it read the wrong config
section. The PR introducing it
(https://github.com/matrix-org/synapse/pull/2301) had feedback suggesting the
name be changed to not re-use the term 'redact' but this wasn't
incorporated.
This reanmes the option to give it a less confusing name, and also
means that people who've set the redact_content option won't suddenly
see a behaviour change when upgrading synapse, but instead can set
include_content if they want to.
This PR also updates the wording of the config comment to clarify
that this has no effect on event_id_only push.
Includes https://github.com/matrix-org/synapse/pull/2422
