Fix end session report, move address when system is a ZC, show #addresses on systems

app/Models/System.php

@@ -47,6 +47,14 @@ class System extends Model
 		return $this->hasOne(Setup::class);
 	}
 
+	/**
+	 * This system is the ZC for the following zones
+	 */
+	public function zcs()
+	{
+		return $this->belongsToMany(Zone::class);
+	}
+
 	/**
 	 * Zones a system has addresses for
 	 *