The new procd config dependency tracking requires the start method to be
called even on boot. So add a state file that is checked by the run script
to condition the special-case boot run instead of the previous independent
call to the run script.

Ref: https://github.com/openwrt/luci/pull/1769

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>

This adds a package wrapping the acme.sh script from
https://github.com/Neilpang/acme.sh in Uci config and hooks to interact
correctly with uhttpd.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>