Create a diagnostic command line argument

[micahellison]

Feature Request

• What is the motivation / use case for changing the behavior?
  Rather than asking users to check their python version, jrnl version, operating system, etc., it would be nice to have a general diagnostic dump that outputs all these values. Maybe it could also output certain non-sensitive values from the configuration (e.g. time format).

• Please provide examples of the usage
  Once finished, we can edit the issue template that was recently made for bugs, and ask users to run this command.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[MinchinWeb]

Should something be added to point people to the issue tracker to submit issues?

[wren]

@MinchinWeb The idea is that once a version with this command is released, we'll update the issue template to ask users to run this command, instead of asking the questions we are currently asking.

It's a good point, though, that we shouldn't close this issue quite yet.