Wiki folder creation case insensitive

Summary

I've noticed this on our instance running at Duke University and gitlab.com:

I currently have a wiki where I created a folder "Meetings" folder (with a capital "M") for our meeting notes locally, and then pushed the wiki back up to Gitlab.

A week later, I created a new page using the interface by typing "Meetings/2017-08-08", and expected another file would be adding to the "Meetings" folder. Instead, a second "meetings" folder was created.

Steps to reproduce

1. Pull wiki, add a new folder, "Meetings", with a markdown file inside, "1.md".
2. From Gitlab.com add a new wiki page entitled "Meetings/2.md"
3. Now you'll have both "Meetings/1.md" and "meetings/2.md" in the wiki.

What is the current bug behavior?

You have both "Meetings/1.md" and "meetings/2.md" in the wiki.

What is the expected correct behavior?

Meetings/
 1.md
 2.md

UI would alert me in case of name conflicts with different cases.

Relevant logs and/or screenshots