This is in preparation for making EventBuilder format agnostic, which
means event signing should be done against the event dict rather than
the EventBuilder object.

Migrate direct message and tag state on room upgrade

* Remove --process-dependency-links from UPGRADE.rst

Signed-off-by: Aaron Raimist <aaron@raim.ist>

* Add changelog

Signed-off-by: Aaron Raimist <aaron@raim.ist>

Refactoring in MatrixFederationAgent

We don't want to be doing .well-known lookups on these guys.

This is going to get too big and unmanageable.

Turns out that the library does a better job of parsing URIs than our
reinvented wheel. Who knew.

There are two things going on here. The first is that, unlike
parse_server_name, URI.fromBytes will strip off square brackets from IPv6
literals, which means that it is valid input to ClientTLSOptionsFactory and
HostnameEndpoint.

The second is that we stay in `bytes` throughout (except for the argument to
ClientTLSOptionsFactory), which avoids the weirdness of (sometimes) ending up
with idna-encoded values being held in `unicode` variables. TBH it probably
would have been ok but it made the tests fragile.

Require event format version to parse or create events

Disable native upsert on sqlite

If you use double-quotes here, you have to escape your backslashes. It's much
easier with single-quotes.

(Note that the existing double-backslashes are already interpreted by python's
""" parsing.)

Move the Host header logic down here so that (a) it is used if we reuse the
agent elsewhere, and (b) we can mess about with it with .well-known.

Ability to search entire room history after upgrading room

Implement MSC 1813 - Add room version to make APIs

Revert "Require event format version to parse or create events"

Require event format version to parse or create events