Added terminal example to exercise rate-limiting functionality

Author: cmaglie

commands/daemon/term_example/go.mod

@@ -0,0 +1,11 @@
+module github.com/arduino/arduino-cli/term_example
+
+go 1.16
+
+replace github.com/arduino/arduino-cli => ../../..
+
+require (
+	github.com/arduino/arduino-cli v0.0.0-20200109150215-ffa84fdaab21
+	google.golang.org/grpc v1.27.0
+	google.golang.org/protobuf v1.25.0
+)