Cyberghost support (#168)

* Host finder CLI for cyberghost
* Resolver program updated with Cyberghost data
* Gluetun cli clientkey subcommand

internal/models/cyberghost.go

@@ -0,0 +1,9 @@
+package models
+
+import "net"
+
+type CyberghostServer struct {
+	Region CyberghostRegion
+	Group  CyberghostGroup
+	IPs    []net.IP
+}