Use UTF8::ucfirst() instead of ucfirst()

`ucfirst()` does not do anything for non-latin characters.

There is no `mb_ucfirst()`.

You could emulate `mb_ucfirst()` with `mb_substr()` and `mb_strtoupper()`.

However Kohana UTF8 helper already has a `UTF8::ucfirst()`.
Merge pull request #44 from OpenBuildings/utf8-ucfirst

Use UTF8::ucfirst() instead of ucfirst()