[BridgeAbstract] Add parameter attribute 'defaultValue'

BridgeAbstract.md

@@ -77,6 +77,7 @@ Parameter Name | Required | Type | Supported values | Description
 `title` | no | Text | | Will be shown as tool-tip when mouse-hovering over the input
 `pattern` | no | Text | | Defines a pattern for an element of type `text`. The required pattern should be mentioned in the `title` attribute!
 `exampleValue` | no | Text | | Defines an example value that is shown for elements of type `text` and `number`
+[`defaultValue`](#defaultvalue) | no | | | Defines the default value.
 
 Hence, the most basic parameter definition is the following :
 
@@ -92,6 +93,15 @@ Hence, the most basic parameter definition is the following :
 ...
 ```
 
+#### defaultValue
+
+This attribute defines the default value for your parameter. Its behavior depends on the `type`:
+
+- `text`: Allows any text
+- `number`: Allows any number
+- `list`: Must match either name or value of one element
+- `checkbox`: Must be "checked" to activate the checkbox
+
 ## The `collectData` function
 
 This function takes as a parameter an array called `$param`, that is automatically filled with values from the user, according to the values defined in the parameters array in `loadMetadatas`.