Implement md5c function, slower than Golang's implementation

keeping it in repo to make further improvements and also rename

        minio-hash ---> crypto

cmd/crypto/.gitignore

@@ -0,0 +1 @@
+crypto

cmd/crypto/crypto.go

@@ -24,8 +24,8 @@ import (
 
 func main() {
 	app := cli.NewApp()
-	app.Name = "minio-hash"
-	app.Usage = ""
+	app.Name = "crypto"
+	app.Usage = "calculate cryptosum on a given stream"
 	app.Commands = Options
 	app.Run(os.Args)
 }

cmd/crypto/crypto.md

@@ -0,0 +1,33 @@
+% MINIO(1) Minio Manual
+% Minio community
+% December 2014
+# NAME
+crypto - calculate crypto sum on a stream
+
+# SYNOPSIS
+
+# DESCRIPTION
+```sh
+NAME:
+   crypto - calculate cryptosum on a given stream
+
+USAGE:
+   crypto [global options] command [command options] [arguments...]
+
+VERSION:
+   0.0.0
+
+COMMANDS:
+   md5sum
+   sha1sum
+   sha256sum
+   sha512sum
+   help, h      Shows a list of commands or help for one command
+
+GLOBAL OPTIONS:
+   --help, -h           show help
+   --version, -v        print the version
+```
+# EXAMPLES
+
+# AUTHORS

cmd/minio-hash/minio-hash.md

@@ -1,13 +0,0 @@
-% MINIO(1) Minio Manual
-% Minio community
-% December 2014
-# NAME
-md5sum - 
-
-# SYNOPSIS
-
-# DESCRIPTION
-
-# EXAMPLES
-
-# AUTHORS