Add nil renderer and combination TUI-daemon program example

The Nil Renderer essentially disables the Bubble Tea renderer sending
loggings and print statements to stdout. It can be enabled via the
ProgramOption WithoutRenderer.

nil_renderer.go

@@ -0,0 +1,9 @@
+package tea
+
+type nilRenderer struct{}
+
+func (n nilRenderer) start()              {}
+func (n nilRenderer) stop()               {}
+func (n nilRenderer) write(v string)      {}
+func (n nilRenderer) altScreen() bool     { return false }
+func (n nilRenderer) setAltScreen(v bool) {}