Update Hass.io docs

source/developers/hassio/addon_testing.markdown

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+---
+layout: page
+title: "Local add-on testing"
+description: "Instructions how to test your add-on locally."
+date: 2017-04-30 13:28
+sidebar: true
+comments: false
+sharing: true
+footer: true
+redirect_from: /hassio/addon_testing/
+---
+
+The fastest way to develop add-ons is by adding them to your local add-on repository. To access your local add-on repository, install either the [Samba add-on] or [SSH add-on].
+
+Right now add-ons will work with images that are stored on Docker Hub (using `image` from add-on config). Without `image` inside local add-ons repository it to be built on the device.
+
+## {% linkable_title Local run %}
+
+You can build an try the addon on your developer machine also. Move all addon stuff into a temp folder. Replace in the Dockerfile `%%BASE_IMAGE%%` with:
+
+- armhf: `homeassistant/armhf-base:latest`
+- aarch64: `homeassistant/aarch64-base:latest`
+- amd64: `homeassistant/amd64-base:latest`
+- i386: `homeassistant/i386-base:latest`
+
+Add also a `LABEL io.hass.version="xy"` into your dockerfile.
+Use `docker` to build the test addon: `docker build -t local/my-test-addon .`
+
+Create a new folder for data and add a test _options.json_ file. After that you can run your add-on with: `docker run --rm -v /tmp/my_test_data:/data -p PORT_STUFF_IF_NEEDED local/my-test-addon`
+
+## {% linkable_title Logs %}
+
+All stdout and stderr is redirected to the Docker logs. The logs can be fetched from the add-on page inside the Hass.io panel in Home Assistant.
+
+[Samba add-on]: /addons/samba/
+[SSH add-on]: /addons/ssh/