Offer choices for graphics drivers, like nvidia vs. nouveau, discrete vs. integrated, etc.

[manuel-192]

Problem:

Setting up graphics drivers during install is currently done under-the-hood. User may want more control over the choices made by the installer.

Additional Notes:

User could be given the choice to choose drivers, e.g.:

• proprietary or open source driver (nvidia, amd)
• permanently use only discrete or integrated card (if available)
• allow switching between discrete and integrated cards (if available)