Hello,

I am encountering some problems with the implementation of the pushd and
popd. The spaces in directory paths should be sanitise so I can read them
properly. This is if I have a folder named Google Drive in my home
directory, I expect it to be `~/Google\ Drive` not `~/Google Drive`, this
is causing me problems to read the data from the `popd -n` because there is
no difference between that whitespace, and the whitespace used to print
elements in the stack.

Best Regards,

João Paulo