Make sure the builtin cd is used.

On my machine cd is an alias that, on success, prints the contents of
the working directory.
Merge pull request #2 from dwijnand/use-builtin-cd

Make sure the builtin cd is used.
Merge branch 'master' of https://github.com/jestor/cdd
cdd.sh still needs to be source'd to affect the current shell
Added directory scrolling when display size is limited