Added an example demonstrating the use of goroutines

examples/goroutines/main.go

@@ -0,0 +1,33 @@
+package main
+
+import "os"
+import "time"
+import "git.tebibyte.media/sashakoshka/tomo"
+import "git.tebibyte.media/sashakoshka/tomo/elements/basic"
+import _ "git.tebibyte.media/sashakoshka/tomo/backends/x"
+
+func main () {
+	tomo.Run(run)
+	os.Exit(0)
+}
+
+func run () {
+	window, _ := tomo.NewWindow(2, 2)
+	window.SetTitle("clock")
+	label := basic.NewLabel(formatTime(), false)
+	window.Adopt(label)
+	window.OnClose(tomo.Stop)
+	window.Show()
+	go tick(label)
+}
+
+func formatTime () (timeString string) {
+	return time.Now().Format("2006-01-02 15:04:05")
+}
+
+func tick (label *basic.Label) {
+	for {
+		label.SetText(formatTime())
+		time.Sleep(time.Second)
+	}
+}