Add Tuya component and platform document (#5739)

* add tuya component and platform document

* add tuya platform ducoment

* remove all platform except switch

* ✏️ Tweaks

source/_components/switch.tuya.markdown

@@ -0,0 +1,23 @@
+---
+layout: page
+title: "Tuya Switch"
+description: "Instructions on how to setup the Tuya switch within Home Assistant."
+date: 2018-07-09 09:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: tuya.png
+ha_category: Switch
+ha_iot_class: "Cloud Polling"
+ha_release: 0.74
+---
+
+
+The `tuya` switch platform allows you to control your [Tuya Smart](https://www.tuya.com) switch.
+
+The platform supports switch and socket.
+
+<p class='note'>
+Full configuration details can be found on the main [Tuya component](/components/tuya/) page.
+</p>

source/_components/tuya.markdown

@@ -0,0 +1,51 @@
+---
+layout: page
+title: "Tuya"
+description: "Instructions on how to setup the Tuya hub within Home Assistant."
+date: 2018-07-09 09:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: tuya.png
+ha_category: Hub
+ha_iot_class: "Cloud Polling"
+ha_release: 0.74
+---
+
+The `tuya` component is the main component to integrate all [Tuya Smart](https://www.tuya.com) related platforms. You will need your Tuya account information (username, password and account country code) to discover and control devices which related to your account.
+
+## {% linkable_title Configuration %}
+
+To add your Tuya devices into your Home Assistant installation, add the following to your `configuration.yaml` file:
+
+```yaml
+tuya:
+  username: YOUR_TUYA_USERNAME
+  password: YOUR_TUYA_PASSWORD
+  country_code: YOUR_ACCOUNT_COUNTRYCODE
+```
+
+{% configuration %}
+username:
+  description: Your username to login to Tuya.
+  required: true
+  type: string
+password:
+  description: Your password to login to Tuya.
+  required: true
+  type: string
+country_code:
+  description: Your account country code (i.e.,1 for USA and 86 for China).
+  required: true
+  type: string
+{% endconfiguration %}
+
+## {% linkable_title Service %}
+
+These services are available for the `tuya` component:
+
+- force_update
+- pull_devices
+
+Devices state data and new devices will refresh automatically. If you want to refresh all devices information or get new devices related to your account manually, you can call the `force_update` or `pull_devices` service.