Resolves #160

The `setup.py` script no longer attempts to install files to privileged
system directories. (Previously, it attempted to do this in order to
enable command-line autocompletion.) In lieu of doing this within the
installer directly, I have simply included brief instructions explaining
how to configure this manually.

Version bumped accordingly.
Merge pull request #165 from chrisallenlane/no-autocomplete

Resolves #160