🏗 Merge C++ into python codebase (#504)

## Description:

Move esphome-core codebase into esphome (and a bunch of other refactors). See https://github.com/esphome/feature-requests/issues/97

Yes this is a shit ton of work and no there's no way to automate it :( But it will be worth it 👍

Progress:
- Core support (file copy etc): 80%
- Base Abstractions (light, switch): ~50%
- Integrations: ~10%
- Working? Yes, (but only with ported components).

Other refactors:
- Moves all codegen related stuff into a single class: `esphome.codegen` (imported as `cg`)
- Rework coroutine syntax
- Move from `component/platform.py` to `domain/component.py` structure as with HA
- Move all defaults out of C++ and into config validation.
- Remove `make_...` helpers from Application class. Reason: Merge conflicts with every single new integration.
- Pointer Variables are stored globally instead of locally in setup(). Reason: stack size limit.

Future work:
- Rework const.py - Move all `CONF_...` into a conf class (usage `conf.UPDATE_INTERVAL` vs `CONF_UPDATE_INTERVAL`). Reason: Less convoluted import block
- Enable loading from `custom_components` folder.

**Related issue (if applicable):** https://github.com/esphome/feature-requests/issues/97

**Pull request in [esphome-docs](https://github.com/esphome/esphome-docs) with documentation (if applicable):** esphome/esphome-docs#<esphome-docs PR number goes here>

## Checklist:
  - [ ] The code change is tested and works locally.
  - [ ] Tests have been added to verify that the new code works (under `tests/` folder).

If user exposed functionality or configuration variables are added/changed:
  - [ ] Documentation added/updated in [esphomedocs](https://github.com/OttoWinter/esphomedocs).

esphome/components/binary_sensor/automation.cpp

@@ -0,0 +1,113 @@
+#include "automation.h"
+#include "esphome/core/log.h"
+
+namespace esphome {
+namespace binary_sensor {
+
+static const char *TAG = "binary_sensor.automation";
+
+void binary_sensor::MultiClickTrigger::on_state_(bool state) {
+  // Handle duplicate events
+  if (state == this->last_state_) {
+    return;
+  }
+  this->last_state_ = state;
+
+  // Cooldown: Do not immediately try matching after having invalid timing
+  if (this->is_in_cooldown_) {
+    return;
+  }
+
+  if (!this->at_index_.has_value()) {
+    // Start matching
+    MultiClickTriggerEvent evt = this->timing_[0];
+    if (evt.state == state) {
+      ESP_LOGV(TAG, "START min=%u max=%u", evt.min_length, evt.max_length);
+      ESP_LOGV(TAG, "Multi Click: Starting multi click action!");
+      this->at_index_ = 1;
+      if (this->timing_.size() == 1 && evt.max_length == 4294967294UL) {
+        this->set_timeout("trigger", evt.min_length, [this]() { this->trigger_(); });
+      } else {
+        this->schedule_is_valid_(evt.min_length);
+        this->schedule_is_not_valid_(evt.max_length);
+      }
+    } else {
+      ESP_LOGV(TAG, "Multi Click: action not started because first level does not match!");
+    }
+
+    return;
+  }
+
+  if (!this->is_valid_) {
+    this->schedule_cooldown_();
+    return;
+  }
+
+  if (*this->at_index_ == this->timing_.size()) {
+    this->trigger_();
+    return;
+  }
+
+  MultiClickTriggerEvent evt = this->timing_[*this->at_index_];
+
+  if (evt.max_length != 4294967294UL) {
+    ESP_LOGV(TAG, "A i=%u min=%u max=%u", *this->at_index_, evt.min_length, evt.max_length);  // NOLINT
+    this->schedule_is_valid_(evt.min_length);
+    this->schedule_is_not_valid_(evt.max_length);
+  } else if (*this->at_index_ + 1 != this->timing_.size()) {
+    ESP_LOGV(TAG, "B i=%u min=%u", *this->at_index_, evt.min_length);  // NOLINT
+    this->cancel_timeout("is_not_valid");
+    this->schedule_is_valid_(evt.min_length);
+  } else {
+    ESP_LOGV(TAG, "C i=%u min=%u", *this->at_index_, evt.min_length);  // NOLINT
+    this->is_valid_ = false;
+    this->cancel_timeout("is_not_valid");
+    this->set_timeout("trigger", evt.min_length, [this]() { this->trigger_(); });
+  }
+
+  *this->at_index_ = *this->at_index_ + 1;
+}
+void binary_sensor::MultiClickTrigger::schedule_cooldown_() {
+  ESP_LOGV(TAG, "Multi Click: Invalid length of press, starting cooldown of %u ms...", this->invalid_cooldown_);
+  this->is_in_cooldown_ = true;
+  this->set_timeout("cooldown", this->invalid_cooldown_, [this]() {
+    ESP_LOGV(TAG, "Multi Click: Cooldown ended, matching is now enabled again.");
+    this->is_in_cooldown_ = false;
+  });
+  this->at_index_.reset();
+  this->cancel_timeout("trigger");
+  this->cancel_timeout("is_valid");
+  this->cancel_timeout("is_not_valid");
+}
+void binary_sensor::MultiClickTrigger::schedule_is_valid_(uint32_t min_length) {
+  this->is_valid_ = false;
+  this->set_timeout("is_valid", min_length, [this]() {
+    ESP_LOGV(TAG, "Multi Click: You can now %s the button.", this->parent_->state ? "RELEASE" : "PRESS");
+    this->is_valid_ = true;
+  });
+}
+void binary_sensor::MultiClickTrigger::schedule_is_not_valid_(uint32_t max_length) {
+  this->set_timeout("is_not_valid", max_length, [this]() {
+    ESP_LOGV(TAG, "Multi Click: You waited too long to %s.", this->parent_->state ? "RELEASE" : "PRESS");
+    this->is_valid_ = false;
+    this->schedule_cooldown_();
+  });
+}
+void binary_sensor::MultiClickTrigger::trigger_() {
+  ESP_LOGV(TAG, "Multi Click: Hooray, multi click is valid. Triggering!");
+  this->at_index_.reset();
+  this->cancel_timeout("trigger");
+  this->cancel_timeout("is_valid");
+  this->cancel_timeout("is_not_valid");
+  this->trigger();
+}
+
+bool match_interval(uint32_t min_length, uint32_t max_length, uint32_t length) {
+  if (max_length == 0) {
+    return length >= min_length;
+  } else {
+    return length >= min_length && length <= max_length;
+  }
+}
+}  // namespace binary_sensor
+}  // namespace esphome