Fixed a few typos

according to the spec of links, I'm not sure whether this should be considered as a shortcut link referencing the ``[info string](#info-string)`` (I would say "no", but without being sure).
Given that the markdown parser used to render the doc online does not consider it as a link (it renders the ``[`` and ``]``) and the target would be the previous sentence, which is a but useless, I decided to remove it.

It could be good to include this snippet as an example in the spec though to ensure consistency:

```
[info string](#info-string)

[info string]
```