Add missing Lovelace Humidifier card docs (#13919)

source/_lovelace/humidifier.markdown

@@ -0,0 +1,35 @@
+---
+title: "Humidifier Card"
+sidebar_label: Humidifier
+description: "The Humidifier card lets you control and monitor humidifiers, dehumidifiers, and hygrostat devices."
+---
+
+The Humidifier card lets you control and monitor humidifiers, dehumidifiers, and hygrostat devices.
+
+{% configuration %}
+type:
+  required: true
+  description: entity
+  type: string
+entity:
+  required: true
+  description: Home Assistant entity ID.
+  type: string
+name:
+  required: false
+  description: Name of Entity
+  type: string
+  default: Entity Name
+theme:
+  required: false
+  description: Set to any theme within `themes.yaml`
+  type: string
+{% endconfiguration %}
+
+## Example
+
+```yaml
+- type: humidifier
+  entity: humidifier.bedroom
+  name: Bedroom Humidifier
+```

source/lovelace/index.markdown

@@ -7,7 +7,7 @@ redirect_from:
 
 Lovelace is the Home Assistant user interface. It's a fast, customizable and powerful way for users to manage their homes, working on mobile or desktop.
 
-- 25 different cards to place and configure as you like.
+- 26 different cards to place and configure as you like.
 - UI Editor. A configuration UI to manage your Lovelace UI including live preview when editing cards.
 - Fast. Using a static configuration allows us to build up the UI once.
 - Customizable.