"Reachability/Reliability" measurement#1673

Basically the same as the other big competitor, this measures the overall connectivity of the monitor on a multi location monitors. The difference with uptime is that this measurment should care if theres some location that cant reach the monitor, lowering the monitors “Reachability/Reliability” percentage, while uptime should only care if any one of the location can reach the monitor or not. This is basically a better version of my other suggestion #1671