Update docs for next release

Author: bhch

docs/docs/schema.md

@@ -3,10 +3,14 @@ layout: page.html
 title: Schema
 ---
 
-This document will be completed in future.
-
-Meanwhile, all the following things have been documented in React JSON Form's sister
-project: [django-jsonform](https://django-jsonform.readthedocs.io/en/latest/).
+<div class="alert alert-info">
+    <p><strong>Note</strong></p>
+    <p>This document will be completed in future.</p>
+    <p>
+        Meanwhile, all the following things have been documented in React JSON Form's sister
+        project: <a href="https://django-jsonform.readthedocs.io/en/latest/">django-jsonform<a>.
+    </p>
+</div>
 
 ## Schema guide
 

docs/docs/usage/node.md

@@ -168,10 +168,26 @@ let errorMap = {
     '0': 'This is required',
 
     // first item > object > property: name
-    '0-name': 'This is required'
+    // (see note below about the section sign "§")
+    '0§name': 'This is required'
 }
 ```
 
+<div class="alert alert-info">
+    <p><strong>The section sign (§)</strong></p>
+    <p>
+        The section sign (<code>§</code>) is used as the separator symbol for
+        doing nested items lookup.
+    </p>
+    <p>
+        Earlier, the hyphen (<code>-</code>) was used but that complicated things
+        when the the schema object properties (i.e. field names) also had a hyphen
+        in them. Then it became impossible to determine whether the hyphen was the
+        separator or part of the key.
+    </p>
+</div>
+
+
 ##### `DataValidator` API reference
 
 ##### Constructor