Summary:
If the `STDIN_FILENO` is a `TTY`, then an interactive command prompt
is shown. Otherwise, client runs in non-interactive mode.
Shell commands start with a colon sign, and end at the end of
line.
Csv and tabular output formats are supported.
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek, mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1633
