Allow addition/deletion of Profile rules

[jack-ullery]

Is your feature request related to a problem? Please describe. Currently there is no way to add/delete rules from the "Profile Modify" page. Users need a way to add/remove abstractions and file rules from a profile.

Describe the solution you'd like I imagine that there could be buttons at the bottom of the screen for adding/deleting a row from the table.

When the delete button is clicked, it should show a popup which will confirm that the user wants to delete a particular rule. When the add button is clicked, it should show a popup with a form that allows the user to configure the new rule.

Describe alternatives you've considered We could additionally trigger addition/deletion operations with accelerator keys. For example, we may want to trigger the deletion popup when the user presses backspace and a row is selected. We could allow inserting a row if the 'i' key is pressed

Additional context I first mentioned this problem in #56

[jack-ullery]

Preliminary progress for this is in origin/issue-63

[jack-ullery]

Close with #83