Update itemsDefault and headerDefault descriptions

To make more consistent with parameterDefault, by request of @webron

Author: earth2marsh

versions/2.0.md

@@ -751,7 +751,7 @@ Field Name | Type | Description
 <a name="itemsFormat"></a>format | `string` | The extending format for the previously mentioned [`type`](#parameterType). See [Data Type Formats](#dataTypeFormat) for further details.
 <a name="itemsItems"></a>items | [Items Object](#itemsObject) | **Required if [`type`](#itemsType) is "array".** Describes the type of items in the array.
 <a name="itemsCollectionFormat"></a>collectionFormat | `string` | Determines the format of the array if type array is used. Possible values are: <ul><li>`csv` - comma separated values `foo,bar`. <li>`ssv` - space separated values `foo bar`. <li>`tsv` - tab separated values `foo\tbar`. <li>`pipes` - pipe separated values <code>foo&#124;bar</code>. </ul> Default value is `csv`.
-<a name="itemsDefault"></a>default | * | Sets a default value to the data type. See http://json-schema.org/latest/json-schema-validation.html#anchor101. Unlike JSON Schema this value MUST conform to the defined [`type`](#itemsType) for the data type.
+<a name="itemsDefault"></a>default | * | Declares the value of the item that the server will use if none is provided. (Note: "default" has no meaning for required items.) See http://json-schema.org/latest/json-schema-validation.html#anchor101. Unlike JSON Schema this value MUST conform to the defined [`type`](#itemsType) for the data type.
 <a name="itemsMaximum"></a>maximum | `number` | See http://json-schema.org/latest/json-schema-validation.html#anchor17.
 <a name="itemsMaximum"></a>exclusiveMaximum | `boolean` | See http://json-schema.org/latest/json-schema-validation.html#anchor17.
 <a name="itemsMinimum"></a>minimum | `number` | See http://json-schema.org/latest/json-schema-validation.html#anchor21.
@@ -1043,7 +1043,7 @@ Field Name | Type | Description
 <a name="headerFormat"></a>format | `string` | The extending format for the previously mentioned [`type`](#stType). See [Data Type Formats](#dataTypeFormat) for further details.
 <a name="headerItems"></a>items | [Items Object](#itemsObject) | **Required if [`type`](#stType) is "array".** Describes the type of items in the array.
 <a name="headerCollectionFormat"></a>collectionFormat | `string` | Determines the format of the array if type array is used. Possible values are: <ul><li>`csv` - comma separated values `foo,bar`. <li>`ssv` - space separated values `foo bar`. <li>`tsv` - tab separated values `foo\tbar`. <li>`pipes` - pipe separated values <code>foo&#124;bar</code>. </ul> Default value is `csv`.
-<a name="headerDefault"></a>default | * | Sets a default value for the header. See http://json-schema.org/latest/json-schema-validation.html#anchor101. Unlike JSON Schema this value MUST conform to the defined [`type`](#headerDefault) for the header.
+<a name="headerDefault"></a>default | * | Declares the value of the header that the server will use if none is provided. (Note: "default" has no meaning for required headers.) See http://json-schema.org/latest/json-schema-validation.html#anchor101. Unlike JSON Schema this value MUST conform to the defined [`type`](#headerDefault) for the header.
 <a name="headerMaximum"></a>maximum | `number` | See http://json-schema.org/latest/json-schema-validation.html#anchor17.
 <a name="headerMaximum"></a>exclusiveMaximum | `boolean` | See http://json-schema.org/latest/json-schema-validation.html#anchor17.
 <a name="headerMinimum"></a>minimum | `number` | See http://json-schema.org/latest/json-schema-validation.html#anchor21.