de-hardcoded the ping target: moved to lime's system section

packages/deferable-reboot/files/etc/uci-defaults/90-cron-defer-reboot

@@ -1,13 +1,11 @@
 #!/bin/sh
 
-internet_gw_ip=4.2.2.2
-
 unique_append()
 {
 	grep -qF "$1" "$2" || echo "$1" >> "$2"
 }
 
 unique_append \
-	"*/3 * * * * ((if ping -c 10 -W 10 $internet_gw_ip &> /dev/null; then awk '{print \$1 + 800}' /proc/uptime > /tmp/deferable-reboot.defer ; fi )&) "\
+	"*/3 * * * * ((if ping -c 10 -W 10 \$(uci -q get lime-autogen.system.deferable_reboot_ping_target) &> /dev/null; then awk '{print \$1 + 800}' /proc/uptime > /tmp/deferable-reboot.defer ; fi )&) "\
 	/etc/crontabs/root
 

packages/lime-docs/files/www/docs/lime-example.txt

@@ -22,6 +22,7 @@ config lime system
 	option root_password_policy 'DO_NOTHING'	# When configured to SET_SECRET, the root password secret will be configured as specified in root_password_secret. When set to RANDOM a strong random password will be set if root has no password, use this if your firmware is built with the ssh keys inside. DO_NOTHING does nothing, leaving the root password empty (you will have to set it manually or through FirstBootWizard).
 	option root_password_secret ''			# This is the password hash as stored in /etc/shadow, it is only used when root_password_policy=SET_SECRET. You can generate the secret with 'openssl passwd -1' to be compatible with most openwrt firmwares, use a strong password with at least 10 numbers and letters, the longer the better!. For improved security use "openssl passwd -6" for SHA512 (or -5 for SHA256) but be aware that not all firmwares support this.
 	option deferable_reboot_uptime_s '97200'
+	option deferable_reboot_ping_target '4.2.2.2' # b.resolvers.Level3.net	# the reboot scheduled by deferable_reboot, if installed, will be deferred if the ping to this IP is succesful
 	option firstbootwizard_configured false
 	option firstbootwizard_dismissed false		# When true fbw banner will be hidden.
 

packages/lime-system/files/etc/config/lime-defaults

@@ -12,6 +12,7 @@ config lime system
 	option root_password_policy 'DO_NOTHING'
 	option root_password_secret ''
 	option deferable_reboot_uptime_s '97200'
+	option deferable_reboot_ping_target '4.2.2.2'
 	option firstbootwizard_configured false
 	option firstbootwizard_dismissed false