Code for Additional Software Packages GUI: Persistence Setup

Originally created by @Anonymous on #14595 (Redmine)

Perl code & consulting for the GUI. (B4)
Preliminary release date for the BETA: April 15th 2018.

The order of priority between these tasks is:

1. implement the API needed by tails-additional-software apt-post so that Alan can keep working on his side:
   1. create persistent volume with ASP enabled
   2. enable ASP
   3. display config
   4. return 0 iff. success
2. fix graphics bug: rectangle filled with black where the list of settings was, after configuring persistence, in the “Finished” window
3. #15259 (closed): Add button in tails-persistence-setup to open the configuration interface of Additional Software
4. #6485 (closed): Support multiple persistent paths per preset in the persistent volume assistant
5. #15314 (closed): Replace custom widget button in persistent wizard with standard GNOME switches
6. #15280 (closed): Reorder persistence features
7. #15313 (closed): Apply changes to persistent features without the need for a Save button

Blueprint: https://tails.boum.org/blueprint/additional_software_packages/gui#index6h2

Feature Branch: perl5lib:feature/14594-asp-gui, iuk:feature/14594-asp-gui, persistence-setup:feature/14594-asp-gui, feature/14594-asp-gui

Parent Task: #14594 (closed)

Subtasks

• #6485 (closed)
• #15259 (closed)
• #15275 (closed)
• #15280 (closed)
• #15314 (closed)
• #15544 (closed)
• #15550 (closed)

Related issues

• Related to sysadmin#15378 (closed)
• Related to #15784 (closed)
• Blocked by #14574 (closed)