Follow symlinks in readdir() and readdirSync()

[caitp]

Closes #14

[caitp]

Let me know if the indentation style used in tests aren't to your linking, not sure if the linter rules will complain if they're not.

This patch will resolve symlinks in the same way open() and stat() will, so I assume it's correct.

[caitp]

This isn't quite ready yet

[caitp]

This feels okay now

[caitp]

there might be an issue here with <link> -> <link> -> <file>-type paths or something

[tschaub]

Thanks for this @caitp! It looks like there might be more work needed to recursively follow links, but I think this is a nice enhancement.

[tschaub]

Published as mock-fs@3.1.0.

[caitp]

Thanks for this @caitp! It looks like there might be more work needed to recursively follow links, but I think this is a nice enhancement.

I sent a followup with a bit more work on this portion --- I believe this matches the typical posix/libc behaviour, but I need to check that as it's been a while