[DOC] slightly reorganize main documentation page

doc/readme.md

@@ -1,63 +1,6 @@
 # 🦉 OWL Documentation 🦉
 
-## Owl Content
-
-Owl is a javascript library that contains some core classes and function to help
-build applications. Here is a complete representation of its content:
-
-```
-owl
-    Component
-    Context
-    QWeb
-    Store
-    useState
-    config
-        mode
-        env
-    core
-        EventBus
-        Observer
-    hooks
-        onWillStart
-        onMounted
-        onWillUpdateProps
-        onWillPatch
-        onPatched
-        onWillUnmount
-        useContext
-        useState
-        useRef
-        useSubEnv
-        useStore
-        useDispatch
-        useGetters
-    misc
-        AsyncRoot
-    router
-        Link
-        RouteComponent
-        Router
-    tags
-        xml
-    utils
-        debounce
-        escape
-        loadJS
-        loadFile
-        shallowEqual
-        whenReady
-```
-
-Note that for convenience, the `useState` hook is also exported at the root of the `owl` object.
-
-## Learning Resources
-
-- [Quick Start: create an (almost) empty Owl application](learning/quick_start.md)
-- [Environment: what it is and what it should contain](learning/environment.md)
-
 ## Reference
-
 - [Animations](reference/animations.md)
 - [Component](reference/component.md)
 - [Configuration](reference/config.md)
@@ -73,6 +16,11 @@ Note that for convenience, the `useState` hook is also exported at the root of t
 - [Tags](reference/tags.md)
 - [Utils](reference/utils.md)
 
+## Learning Resources
+
+- [Quick Start: create an (almost) empty Owl application](learning/quick_start.md)
+- [Environment: what it is and what it should contain](learning/environment.md)
+
 ## Miscellaneous
 
 - [Comparison with React/Vue](comparison.md)
@@ -81,8 +29,45 @@ Note that for convenience, the `useState` hook is also exported at the root of t
 
 ## Architecture
 
-This section explains in more detail the inner workings of Owl. It is more
+This section explains in more detail the inner workings of Owl. It is targeted
-useful for people working on Owl code.
+for developers working on Owl itself.
 
 - [Virtual DOM](architecture/vdom.md)
 - [Rendering](architecture/rendering.md)
+
+## Owl Content
+
+Here is a complete visual representation of everything exported by the `owl`
+global object (so, for example, `Component` is available at `owl.Component`,
+and `EventBus` is exported as `owl.core.EventBus`):
+
+```
+Component                               misc
+Context                                     AsyncRoot 
+QWeb                                    router
+Store                                       Link
+useState                                    RouteComponent
+config                                      Router
+    mode                                tags
+    env                                     xml
+core                                    utils
+    EventBus                                debounce
+    Observer                                escape
+hooks                                       loadJS
+    onWillStart                             loadFile
+    onMounted                               shallowEqual
+    onWillUpdateProps                       whenReady
+    onWillPatch
+    onPatched
+    onWillUnmount
+    useContext
+    useState
+    useRef
+    useSubEnv
+    useStore
+    useDispatch
+    useGetters
+```
+
+Note that for convenience, the `useState` hook is also exported at the root of the `owl` object.
+