Correctly encode and decode strings in convert_html_to_markdown.
It wasn't possible to use universal_newlines=True since
Popen.communicate doesn't encode/decode strings correctly on
python 2.
Bitbucket changed the format of their API. The old format is still
useful for BitBucket enterprise, but for the main cloud verison of
Bitbucket, we need a new BitBucket integration supporting the new API.
Several recently merged webhooks were incorrectly not checking that
the actual webhook result didn't return an error. While they would
usually still fail in most cases when checking whether the message
came back correctly, this hid the root cause errors and thus made it
much harder to debug.
This integration relies on the Teamcity "tcWebHooks" plugin which is
available at
https://netwolfuk.wordpress.com/category/teamcity/tcplugins/tcwebhooks/
It posts build fail and success notifications to a stream specified in
the webhook URL.
It uses the name of the build configuration as the topic.
For personal builds, it tries to map the Teamcity username to a Zulip
username, and sends a private message to that person.