Add select entities and implement template select (#2067)

Co-authored-by: Otto Winter <otto@otto-winter.com>

esphome/components/select/automation.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include "esphome/core/automation.h"
+#include "esphome/core/component.h"
+#include "select.h"
+
+namespace esphome {
+namespace select {
+
+class SelectStateTrigger : public Trigger<std::string> {
+ public:
+  explicit SelectStateTrigger(Select *parent) {
+    parent->add_on_state_callback([this](std::string value) { this->trigger(std::move(value)); });
+  }
+};
+
+template<typename... Ts> class SelectSetAction : public Action<Ts...> {
+ public:
+  SelectSetAction(Select *select) : select_(select) {}
+  TEMPLATABLE_VALUE(std::string, option)
+
+  void play(Ts... x) override {
+    auto call = this->select_->make_call();
+    call.set_option(this->option_.value(x...));
+    call.perform();
+  }
+
+ protected:
+  Select *select_;
+};
+
+}  // namespace select
+}  // namespace esphome