Update rst.html.markdown

Revising the section on creating lists with RST, as the syntax for list/sublist creation is not 1-1 with Markdown. 

The current example is actually incorrect—any/all sublists must be separated from their parent list by blank lines (above and below). These sublists must also be properly indented in relation to the text of the above parent list.

References: 
[1]: http://docutils.sourceforge.net/docs/ref/rst/restructuredtext.html#bullet-lists
[2]: http://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html

rst.html.markdown

@@ -47,19 +47,25 @@ Title are underlined with equals signs too
 Subtitles with dashes
 ---------------------
 
-You can  put text in *italic* or in **bold**, you can "mark" text as code with double backquote ``print()``.
+You can put text in *italic* or in **bold**, you can "mark" text as code with double backquote ``print()``.
 
-Lists are as simple as in Markdown:
+Lists are similar to Markdown, but a little more involved—remember to line up list symbols (like - or *) with the left edge of the previous text block, and remember to use blank lines to separate new lists from parent lists.    
 
 - First item
 - Second item
-    - Sub item
+
+  - Sub item
+    
+- Third item
 
 or
 
 * First item
 * Second item
-    * Sub item
+    
+  * Sub item
+
+* Third item
 
 Tables are really easy to write: