Revert "delete everything" (includes everything non-go-crypto)

This reverts commit 96a3502

node/id.go

@@ -0,0 +1,35 @@
+package node
+
+import (
+	"time"
+
+	"github.com/tendermint/tendermint/crypto"
+)
+
+type NodeID struct {
+	Name   string
+	PubKey crypto.PubKey
+}
+
+type PrivNodeID struct {
+	NodeID
+	PrivKey crypto.PrivKey
+}
+
+type NodeGreeting struct {
+	NodeID
+	Version string
+	ChainID string
+	Message string
+	Time    time.Time
+}
+
+type SignedNodeGreeting struct {
+	NodeGreeting
+	Signature crypto.Signature
+}
+
+func (pnid *PrivNodeID) SignGreeting() *SignedNodeGreeting {
+	//greeting := NodeGreeting{}
+	return nil
+}