Support in-place upgrades of new minio binary and releases. (#4961)

This PR allows 'minio update' to not only shows update banner
but also allows for in-place upgrades.

Updates are done safely by validating the downloaded
sha256 of the binary.

Fixes #4781

vendor/github.com/howeyc/gopass/terminal.go

@@ -0,0 +1,25 @@
+// +build !solaris
+
+package gopass
+
+import "golang.org/x/crypto/ssh/terminal"
+
+type terminalState struct {
+	state *terminal.State
+}
+
+func isTerminal(fd uintptr) bool {
+	return terminal.IsTerminal(int(fd))
+}
+
+func makeRaw(fd uintptr) (*terminalState, error) {
+	state, err := terminal.MakeRaw(int(fd))
+
+	return &terminalState{
+		state: state,
+	}, err
+}
+
+func restore(fd uintptr, oldState *terminalState) error {
+	return terminal.Restore(int(fd), oldState.state)
+}