feat: add option to sort items in properties shortcode (#527)

BREAKING CHANGE: To enable sorting of elements in the `properties` shortcode, it was necessary to change the structure of the properties file. Due to this change, the `properties` object now requires a list of maps instead of a map. A [sample file](https://raw.githubusercontent.com/thegeeklab/hugo-geekdoc/main/exampleSite/data/properties/demo.yaml) can be found in the repository.

exampleSite/data/properties/demo.yaml

@@ -1,11 +1,11 @@
 ---
 properties:
-  prop1:
+  - name: prop1
     type: string
     description: Dummy description of the prop1 string property.
     required: true
 
-  prop2:
+  - name: prop2
     type: int
     defaultValue: 10
     description:
@@ -16,7 +16,7 @@ properties:
         - tag1
         - tag2
 
-  prop3:
+  - name: prop3
     type: bool
     defaultValue: false
     description: |
@@ -27,3 +27,8 @@ properties:
 
       More description how to use this property.
     required: false
+
+  - name: a-prop
+    type: string
+    description: Property to demonstrate sorting.
+    required: true