Component decorators (#354)

Add decorator variants for decorator components

Add the "pipe" operator for components, similar to what was done for Elements.
We are able to put something like:
```
Button(...) | Maybe(&show_button)
```

Add decorators for:
- `Maybe`
- `CatchEvent`
- `Renderer`

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>

src/ftxui/component/util.cpp

@@ -0,0 +1,32 @@
+#include <functional>  // for function
+#include <memory>      // for __shared_ptr_access
+
+#include "ftxui/component/component.hpp"  // for ElementDecorator, Renderer, ComponentDecorator, operator|, operator|=
+#include "ftxui/component/component_base.hpp"  // for Component, ComponentBase
+#include "ftxui/dom/elements.hpp"              // for Element
+
+namespace ftxui {
+
+Component operator|(Component component, ComponentDecorator decorator) {
+  return decorator(component);
+}
+
+Component operator|(Component component, ElementDecorator decorator) {
+  return component | Renderer(decorator);
+}
+
+Component& operator|=(Component& component, ComponentDecorator decorator) {
+  component = component | decorator;
+  return component;
+}
+
+Component& operator|=(Component& component, ElementDecorator decorator) {
+  component = component | decorator;
+  return component;
+}
+
+}  // namespace ftxui
+
+// Copyright 2022 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.