Extend installation steps with sudo-able paths

[LoyVanBeek]

Fixes #30

[jbpratt]

Hey @LoyVanBeek , it seems that the project has updated it's name. Would you mind making the changes to reflect this?

[LoyVanBeek]

Bandwhich, great name. PR is updated.

[imsnif]

Great work collecting all the solutions!

I would very much like to add it to the README (I think it will save people a lot of time opening and responding to issues), but maybe we can have it in its own special Troubleshooting section?

Maybe between "raw_mode" and "Contributing" (on the same header level as "Contributing")?
Then this can be under a sub-header of "Installing with Cargo" or something else you feel makes sense? What say you?

[LoyVanBeek]

These staps ere required to get bandwhich working at all, so I'd considered them part of installation. Troubleshooting would be for other types of problems perhaps.

[Calinou]

I've opened #57, which may be an easier solution than the one proposed here. I don't think it works on macOS though, so we may want to document both.

[imsnif]

@LoyVanBeek - fair point :)

I moved some stuff around your changes to make things clearer. Thank you very much for this!