Add "reassess initiative" option

[dave-mills]

Is your feature request related to a problem? Please describe. We should expose the "reassess this initiative" option on the front-end.

[dave-mills]

Notes:

• There is currently a "reassess" function on ProjectCrudController that's linked to a route. We need to:
• [x] Add a link on the main initiatives list page and on the show initiative page to expose this functionality to the user.
  • There should be a confirmation dialog for the user which clearly states what will happen ('the current assessment will be archived and the initiative will be reset to the beginning, allowing you to complete the assessment process again based on the current status of the initiative')
• [x] The re-assess function was written a while ago, so it needs to be checked against the code that's run when a new initiative is created.
• [x] We should present an option to review past assessments on initiatives that have multiple linked assessments. I think this should be a list of past assessments shown somewhere on the "show initiative" page, that gives links to show a version of the show initiative page for any previous assessment.