_frontend/app.py: Set correct element-path in interactive bst-init

See merge request !912

Benjamin Schubert authored Oct 19, 2018 and Benjamin Schubert committed Nov 01, 2018

This includes a new command mimicking pytest-runner so that we
can drop this dependency

This was the only setup_requires dependency that we had and
will make like easier for people behind proxies

Remove dependency on pytest-runner

See merge request !886

This feature is useful when bootstraping a system.