Improved chnroutes to also easily delete rules
Improved chnroutes to also easily delete rules

Doesn't change previous behaviour, by using sane
defaults so doesn't break backwards compatiblity
with people already using the scripts.

You can simple delete added rules with
./chnroutes.sh down

And adding with either `chnroutes.sh add` or just `chnroutes.sh`

bjrara/ShadowVPN,noikiy/ShadowVPN,test1943/ShadowVPN,noikiy/ShadowVPN,sunclx/ShadowVPN,sunclx/ShadowVPN,froggatt/ShadowVPN,froggatt/ShadowVPN,bjrara/ShadowVPN,test1943/ShadowVPN