v0.4.1

* Use `shr` to render HTML instead of `html2text`. The results are mostly
positive, but it has a weird effect on emoji/non-ascii characters. For example,
a :sunglasses: emoji will be rendered as "p." Weird.
* `mastodon-version` function uses new `mastodon-version` const. Deleted the
  `.version` file.
* New line issues should be fixed (#48)
* Mentions are parsed correctly, showing just @handle (#42)