Code review comment for lp:~frankban/juju-quickstart/remove-jenv

Reviewers: mp+246162_code.launchpad.net,

Message:
Please take a look.

Description:
Jenv files removal functionality.

Add the ability to remove jenv files
from the Juju home.

Test: `make check`.

QA:
- `juju bootstrap` an environment;
- create a new user for the environment:
   `juju user add myuser --generate -o ~/.juju/environments/myenv`;
- run quickstart in interactive mode:
   `.venv/bin/python juju-quickstart -i`;
- the "myenv" environment should be listed under
   "Other active environments": select it;
- ensure the corresponding environment description in
   the jenv detail view makes sense;
- click to remove the environment, cancel the removal in the
   confirm dialog and ensure the environment is still there;
- click the "remove" button again, confirm the deletion and
   ensure that a message is displayed and the environment
   file has been deleted. Also quickstart redirects to the
   environments index view and "myenv" is no longer there;
- destroy the environment: done, thank you!

https://code.launchpad.net/~frankban/juju-quickstart/remove-jenv/+merge/246162

(do not edit description out of merge proposal)

Please review this at https://codereview.appspot.com/189540043/

Affected files (+200, -38 lines):
   A [revision details]
   M quickstart/cli/params.py
   M quickstart/cli/views.py
   M quickstart/manage.py
   M quickstart/models/jenv.py
   M quickstart/tests/cli/test_params.py
   M quickstart/tests/cli/test_views.py
   M quickstart/tests/models/test_jenv.py
   M quickstart/tests/test_manage.py