* py3 fixes for federation_client
* .well-known support for federation_client

* Fix check-newsfragment script

I previously broke this so that it always succeeded...

* more fixes

* fix newsfiles

* You need an entry in the debian changelog (and not a regular newsfragment)
  for debian packaging changes.
* Regular newsfragments must end in full stops.

Rewrite this in python so that it can be run in parallel.

Broadly three things here:

* disable W504 which seems a bit whacko
* remove a bunch of `as e` expressions from exception handlers that don't use
  them
* use `r""` for strings which include backslashes

Also, we don't use pep8 any more, so we can get rid of the duplicate config
there.

Signed-off-by: Schnuffle <schnuffle@github.com>

* changelog

* reduce circleci config

* plus a handy script

* fix regex

The problem with this script is that it is largely untested, entirely
unmaintained, and running it is likely to make your synapse blow up in
exciting ways.

For example, it leaves a bunch of tables with dead values in it, like
event_to_state_groups.

Having it here sends a message that it is a supported part of
synapse, which is absolutely not the case.

This appears to have stopped working since matrix.org moved to cloudflare. The
Host header should match the name of the server, not whatever is in the SRV
record.

so that you don't necessarily need a config file.

Make it read the config file, primarily.

Signed-off-by: Christian W. Zuckschwerdt <christian@zuckschwerdt.org>

synapse

This is necessary for replicating the data in synapse to be visible to a
separate service because presence and typing notifications aren't stored
in a database so won't be visible to another process.

This API can be used to either get the raw data by requesting the tables
themselves or to just receive notifications for updates by following the
streams meta-stream.

Returns updates for each table requested a JSON array of arrays with a
row for each row in the table.

Each table is prefixed by a header row with the: name of the table,
current stream_id position for the table, number of rows, number of
columns and the names of the columns.
This is followed by the rows that have been added to the server since
the requester last asked.

The API has a timeout and is hooked up to the notifier so that a slave
can long poll for updates.