begin refactor of proxy engine

proxychain/rqm/spoof_x_forwarded_for.go

@@ -0,0 +1,14 @@
+package rqm // ReQuestModifier
+
+import (
+	"ladder/proxychain"
+)
+
+// SpoofXForwardedFor modifies the X-Forwarded-For header
+// in some cases, a forward proxy may interpret this as the source IP
+func SpoofXForwardedFor(ip string) proxychain.RequestModification {
+	return func(px *proxychain.ProxyChain) error {
+		px.Request.Header.Set("X-FORWARDED-FOR", ip)
+		return nil
+	}
+}