To avoid potential issues with USBMS.
Namely, make sure CWD doesn't point to the userstore for persitent
processes.
Make sure wpa_supplicant doesn't try to use our own OpenSSL lib, which,
again, is in the userstore area.
Properly kill our dhcp client invocation on when killing WiFi
Also, some related fixes to the startup script:
Properly kill wpa_supplicant & the dhcp client when we kill
wifi before rebooting to nickel.
For some unknowable reason, restarting nickel on exit deadlocks on my
H2O, so, do a full reboot instead, at least *that* works.
I'm probably one of the only people running KO manually anyway...
