Split example.org into separate files

... hopefully correctly

This will hopefully improve ease of developing (more granular test results) and
prepares us for adding example org->html renders for gh-pages

org/testdata/lists.org

@@ -0,0 +1,20 @@
+- unordered list item 1
+- unordered list item 2 - with ~inline~ /markup/
+  1. ordered sublist item 1
+     a) ordered sublist item 1
+     b) ordered sublist item 2
+     c) ordered sublist item 3
+  2. ordered sublist item 2
+- unordered list item 3 - and a [[https://example.com][link]]
+  and some lines of text
+  1. and another subitem
+     #+BEGIN_SRC sh
+     echo with a block
+     #+END_SRC
+  2. and another one with a table
+     | a | b | c |
+     |---+---+---|
+     | 1 | 2 | 3 |
+
+     and text with an empty line in between as well!
+- unordered list item 4