Elm module names are case-insensitive on Windows/OS X, case sensitive on Linux

[eeue56]

Example:

File b.elm

module B where
f = identity

File a.elm

import B

On Windows and OS X), there will be no error and it will work even though the file is called b.elm, not B.elm. On case-sensitive operating systems (Linux) it will create an error.

Expected behaviour should be that an error is raised on Windows too, or at least a warning.

[aaronwhite]

Oddly, enough, I'm running into this problem in a sort of reverse! (Elm 0.17)

On my mac OSX 10.12 import App.Model in Main correctly resolves file app/model.elm however in CircleCI (Ubuntu 14.04) it fails to find App.Model ..... unless I rename the directories and capitalize them.

I'd actually prefer case insensitivity for matching module names with folders, but either way, it's painful for us now having to remember to bend our local environments because downstream the CI machine doesn't like our lower-cased folder names.