Add and remove apps from favorites within launcher

[relic-se]

Currently, it requires manual editing of launcher.config.json to add applications to your favorites list. I think it would be a great improvement to UX to add an application to the top of the favorites list via user input. A heart icon could be displayed in the top right corner of the app icon to indicate that it is in the user's favorites list.

This action could be executed in the following ways:

• Keyboard: Pressing "f" when the app is highlighted.
• Mouse: An empty heart icon could be displayed when the app icon is hovered over and clicking on that icon would add the app to the list and update the icon.
• Gamepad: Either X or Y could be used or even a combo input (ie: Select+X) when the app is highlighted.

These actions could work to remove the application from the favorites list as well.