Update Arch Linux instructions

[lucaswerkmeister]

The current Arch Linux instructions on the website read:

Arch linux

pacaur -S keybase-bin  # or your preferred AUR install method
run_keybase

Remember to run_keybase after you install or upgrade Keybase.

Note: the community/keybase and community/kbfs packages also exist, but they don't include the GUI or the run_keybase script, and they require more manual setup.

These instructions are a bit outdated:

• The pacaur AUR helper is no longer maintained. There is of course no one replacement, and we can bikeshed all day about which AUR helper to recommend, but aurman seems to be a popular one which still uses the same syntax (i. e. aurman -S keybase-bin works).

• There is also a community/keybase-gui package. I now have the three packages from community/ installed, instead of keybase-bin, and they seem to be working fine. However, that’s on a system where Keybase was already set up previously (I reinstalled Linux but backed up my dotfiles, so ~/.config/keybase etc. were still there), so I can’t say anything about the setup required.

• (While we’re at it – the Linux in Arch Linux is usually capitalized.)

[nstgc]

I would also like to point out that it would be helpful if the bit about executing run_keybase mentions too that you can instead systemctl start --user keybase kbfs instead.