generate: Reorder the items

Signed-off-by: Ce Gao <ce.gao@outlook.com>

Author: gaocegege

content/README.md

@@ -1,4 +1,11 @@
 # Processing.R Documentation
 
 The documentation is genrated by [Processing.R-docs-tools](https://github.com/processing-r/Processing.R-docs-tools). If you want to update the documantion, please use the tools.
- 
+
+You could use [static-server](https://www.npmjs.com/package/static-server) to preview the documentaion in localhost:
+
+```bash
+$ npm install -g static-server
+$ static-server -p 8123
+$ # View localhost:8123
+```

src/generate.py

@@ -84,20 +84,20 @@ def render_reference_index(self):
             ('Structure', ''),
             ('Environment', ''),
             ('Control', ''),
-            ('Shape', ''),
-            ('Shape', '2D Primitives'),
-            ('Shape', 'Curves'),
-            ('Shape', '3D Primitives'),
-            ('Shape', 'Attributes'),
-            ('Shape', 'Vertex'),
-            ('Shape', 'Loading & Displaying'),
             ('Input', 'Mouse'),
             ('Input', 'Keyboard'),
             ('Input', 'Files'),
             ('Input', 'Time & Date'),
             ('Output', 'Text Area'),
             ('Output', 'Image'),
             ('Output', 'Files'),
+            ('Shape', ''),
+            ('Shape', '2D Primitives'),
+            ('Shape', 'Curves'),
+            ('Shape', '3D Primitives'),
+            ('Shape', 'Attributes'),
+            ('Shape', 'Vertex'),
+            ('Shape', 'Loading & Displaying'),
             ('Transform', ''),
             ('Lights, Camera', 'Lights'),
             ('Lights, Camera', 'Camera'),