Do not transform the capitalisation of custom titles

[coconup]

I am customising my table of contents as follows:

---
items:
  - path: api-docs
    title: API docs
---

I would expect this to render as "API docs", but instead I get "Api Docs".

I think it would make more sense to leave titles as they are, if they have been specified by the user.

EDIT: it seems this only happens when the child page also has a --- ... --- block at the top of the document.