Implement Public, Friends, and Private Access to Archives

[dsu1]

Allow users to set an archive to public, private, or friends. Default should be to private.

Tasks:

• Add a viewable field to the archives table which only accept the strings: public, private, or friends
• Add archive validations to check for this field in the Model
• Add this 'viewable' field to the strong parameter check in the Archives Controller
  • Add the necessary parameters that is sent to the controller
• Add this as radio buttons to Archive Creation view