Add delete function to export view

[Ed McDonagh]

Refs #19

[Ed McDonagh]

Starting to add in a form to the exports list. Refs #90

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[Ed McDonagh]

Added the form elements to the exports template, currently using a GET, plan to change this to a POST. Added view url to urls, started to add delete view to ajaxviews. Refs #90.

→ <<cset 9d063f0e3122>>

[Ed McDonagh]

Delete of export file and database records now work. TODO: Change to POST, add authorisation, styling and add in some try statements to allow for failure. Refs #90.

→ <<cset dd4545d25ab9>>

[Ed McDonagh]

Styled delete checkbox and delete submit button. Also hide submit button unless there is something in the table. Refs #90.

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[Ed McDonagh]

Added login_required decorator to prevent situation where logged in user logs out, then back button is used to get back to the exports page and an non-authorised user could delete exports. Refs #90

→ <<cset 599f8ef6574f>>

[Ed McDonagh]

Added exception capture on file delete with success or error message being passed through to be displayed stylised on the exports page of the interface. Refs #90

→ <<cset 4e6a6e22029b>>

[Ed McDonagh]

Delete exports function added. Fixes #90.

→ <<cset 75791d4d30fc>>

[Ed McDonagh]

Updating changes.rst ref #90.

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