Delete survey submission

[niklasva82]

• Adds action and reducer for deletion of survey submission.
• Adds delete link to survey submission which opens ConfirmDeletePane.
• Extends ConfirmDeletePane to handle survey submissions.

Resolves #665

[richardolsson]

In case anyone's interested, here is how I tested that this works and does what one would expected.

I set up a call assignment to quickly respond to the survey that is part of the dummy data, on behalf of six dummy people. I then created three Smart Search queries, one of each type that is related to survey submissions: survey_submission, survey_response and survey_option.

I then set up a view containing columns for the three smart searches, and one of each of the view columns that relate to survey submissions. I added all the six respondents to the view.

I then tried to delete two submissions, and looked at the view to verify that all indications of the submissions ever having existed were no longer in the view:

This way, it tests both the deleting itself, but also the survey-related Smart Search and view features.