no issue
- https://github.com/mochajs/mocha/blob/master/CHANGELOG.md#400--2017-10-02
- the new `--exit` flag might be interesting at some point
> In Mocha v3.0.0 and newer, returning a Promise and calling done() will result in an exception.
- adapt teardown/setup test utility
- adapt other mixed usages of callback && Promise usage
closes#8568
- use our `urlJoin` util to concatenate the URL (not the query part of it, as this is not supported in `urlJoin`) and to prevent possible missing or double slashes, as `config.apiUrl` could be with or without trailing slash
closes#8479
- removes `markdown` field from schema
- removes `legacyMarkdown` converter
- updates tests to work with `mobiledoc` field instead of `markdown` and adapt for mobiledoc HTML output where necessary
