Stickler push reported file non-readable when the file actually didn't exist

[sylnp0201]

When I tried to sticker push my gem with a typo in the gem file name, I got "[file name] must be readable". It took me sometime to figure out in fact the file name actually didn't exist. It would be nice if the error message reflects the issue more accurately such as "[file name] doesn't exists."

[copiousfreetime]

sounds reasonable, I think I can make that happen.