Create add permission workflow

[ethanfrech]

Due: 11/02/2022

Definition of done:

• When clicking "add" button, create popup form #238
• Popup form will contain a text input box to add users (email addresses) to file #239
• Popup form will contain a dropdown to select role (editor, viewer, and commenter) #240
• Popup form will contain a confirmation button #241
• After confirming action, send user back to file explorer #244
• Add function to post data from user input to the back end #299

[ethanfrech]

Request #241 and #244 are closed by pull request #296.

[ethanfrech]

Spent 2 hours finding, implementing and modifying a bootstrap modal.

[ethanfrech]

Spent 4 hours setting up functions to get and format data from the user input and then posting it to the back end.