Originally reported as #446

Node version (or tell us if you're using electron or some other framework):

latest

ShellJS version (the most recent version/Github branch you see the bug on):

Latest. The bug was introduced in v0.7.0

Operating system:

Confirmed on both OS X and Linux.

Description of the bug:

Originally reported in #446. I'm branching this off, since that issue actually discusses two changes.

ls() doesn't follow symlinks pointing to directories, while ls does in Bash.

Example ShellJS command to reproduce the error:

// setup
shell.mkdir('real');
shell.touch('real/file1');
shell.touch('real/file2');
shell.ln('-s', 'real', 'sym');

shell.ls('real');      // file1, file2
shell.ls('sym');       // sym (this is a bug)
shell.exec('ls real'); // file1, file2 (bash behavior)
shell.exec('ls sym');  // file1, file2 (bash behavior)

@freitagbr can you investigate? We should bisect to find the commit that introduced this bug (possibly something from this list). From there, we can figure out how to fix this.