_pkg.dev: drop the last wire/util code

SumSHA256() and ReaderToBuffer() are not used, CalculateHash() shouldn't be
used and BufferLength() is just to easy with only one user.

_pkg.dev/wire/message.go

@@ -47,7 +47,7 @@ func WriteMessage(w io.Writer, magic protocol.Magic, message Messager) error {
 		return err
 	}
 
-	payloadLen := util.BufferLength(buf)
+	payloadLen := uint32(buf.Len())
 	checksum := checksum.FromBytes(buf.Bytes())
 
 	bw.Write(payloadLen)

_pkg.dev/wire/util/util.go

@@ -1,49 +0,0 @@
-package util
-
-import (
-	"bytes"
-	"crypto/sha256"
-
-	"io"
-	"io/ioutil"
-)
-
-// Convenience function
-
-// BufferLength returns the length of a buffer as uint32
-func BufferLength(buf *bytes.Buffer) uint32 {
-
-	return uint32(buf.Len())
-}
-
-// SumSHA256 returns the sha256 sum of the data
-func SumSHA256(b []byte) []byte {
-	h := sha256.New()
-	h.Write(b)
-	return h.Sum(nil)
-}
-
-// CalculateHash takes a function with a binary writer and returns
-// the double hash of the io.Writer
-func CalculateHash(f func(bw *BinWriter)) (Uint256, error) {
-	buf := new(bytes.Buffer)
-	bw := &BinWriter{W: buf}
-
-	f(bw)
-
-	var hash Uint256
-	hash = sha256.Sum256(buf.Bytes())
-	hash = sha256.Sum256(hash.Bytes())
-	return hash, bw.Err
-
-}
-
-//ReaderToBuffer converts a io.Reader into a bytes.Buffer
-func ReaderToBuffer(r io.Reader) (*bytes.Buffer, error) {
-	byt, err := ioutil.ReadAll(r)
-	if err != nil {
-		return nil, err
-	}
-	buf := bytes.NewBuffer(byt)
-	return buf, nil
-}