Feature Request: Add warning when including files with nonmatching case

[StanHash]

The problem

Let's say we have the file EAstdlib.event; but the user writes this (and a good amount of users seem to write this):

#include "eastdlib.event" // not the same case!

If eastdlib.event is a file that exists, then all is good. But if not, this will include EAstdlib.event on Windows; but on Linux this will fail.

Inconsistent behaviour across different platforms... 😠

The suggested solution

Add a warning when the user is including a file that Core can find; but whose actual filename doesn't match.

This has the advantage of not actually breaking existing events while still notifying the user than something is wrong.

Of course this would make a lot of common events emit warnings; which may be unwanted (I don't think so personally).

The other solution to this problem I can think of is to try and find the file in a case independent way across all platforms. (I guess this would be "fixing" the assembler instead of the events; I don't really like that but I guess it's up to discussion).