## Description:


**Related issue (if applicable):** fixes <link to issue>

**Pull request in [esphomedocs](https://github.com/OttoWinter/esphomedocs) with documentation (if applicable):** OttoWinter/esphomedocs#<esphomedocs PR number goes here>
**Pull request in [esphomelib](https://github.com/OttoWinter/esphomelib) with C++ framework changes (if applicable):** OttoWinter/esphomelib#<esphomelib PR number goes here>

## Example entry for YAML configuration (if applicable):
```yaml

```

## Checklist:
  - [ ] The code change is tested and works locally.
  - [ ] Tests have been added to verify that the new code works (under `tests/` folder).
  - [ ] Check this box if you have read, understand, comply, and agree with the [Code of Conduct](https://github.com/OttoWinter/esphomeyaml/blob/master/CODE_OF_CONDUCT.md).

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