Displayed Return Types in Info Panel are incorrect

[baronfel]

The problem is with the regexes that we use in the documentation formatter, they are too greedy.

A proper fix would be to not format the type signatures as postfix types (int list) instead of prefix types (list), but this doesn't currently exist in FCS. This PR adds such a facility, and when it's available we should make use of it.

[baronfel]

The backing PR has been merged, and now we're just waiting on a version of FCS to be made available containing the fix.

[baronfel]

We've updated FCS and incorporated the use of the new formatting flag so that we don't have to regex-replace the types anymore, so this can be closed.