Files with hyphenated filenames are silently ignored, should produce error

[glennsl]

Files with hyphenated filenames, e.g. foo-bar.re are silently ignored by bsb. I've learned that this is because files are modules and hyphens are invalid in module names. It should therefore cause an error, but because they are ignored the errors eventually produced will be very confusing.

[glennsl]

Another possibility is to just transform the hyphenated filenames into PascalCase. Should be pretty straightforward. So foo-bar.re becomes FooBar. This might of course lead to conflicts with another file named fooBar.re, but this problem already exists with with FooBar.re also being a valid filename that all are translated to the same module name.

[bobzhang]

I will add a warning in next release, let's avoid name mangling unless we have to : )