Avoid accidental escaped bullet points

It's common to see bullet points that are a little off get reflow/remarked as literal dashes. For example something like

```
- Blah blah blah blah blah blah.
- Blah blah.
```

turns into

```
- Blah blah blah blah blah blah.
\- Blah blah.
```

We should figure out a way to make this less common and annoying. It's very rare to have a sentence begin with a literal dash.