Make it so that, before there is a power-levels event in the room, you need a
power level of at least 50 to send state.

Partially addresses https://github.com/matrix-org/matrix-doc/issues/1192

stop pretending that it returns a boolean, which just almost gave me a heart
attack.

it makes it easier for me to reason about

fix bug introduced in #3256

federation: fix LaterGauge usage

Fixes a startup crash due to commit df9f72d9
"replacing portions".

Add private IPv6 addresses to example config for url preview blacklist

daily user type phone home stats

Ignore depth when updating read-receipts

Order read receipts by stream ordering instead of depth

The added addresses are expected to be local or loopback addresses and
shouldn't be spidered for previews.

Signed-off-by: Felix Schäfer <felix@thegcat.net>

Consistently use six's iteritems and wrap lazy keys/values in list() if they're not meant to be lazy (#3307)

use memoryview in py3

remaining isintance fixes

Exempt AS-registered users from doing gdpr

extend tox testing for py3 to avoid regressions

Signed-off-by: Adrian Tschira <nota@notafile.com>