Handling of lists is buggy (wrong indentation)

[aplteam]

This illustrates the problem:

1. This example...

1. ... illustrates a bug in MarkAPL's handling of nested lists

   1. This is nested
      
      some code

      
      ... but this is shown left-aligned when it shouldn't! It probably also breaks the list which would explain why the next topic is shown on the wrong level.

   2. Bla bla

      ```
      some more code
      ```

1. This is **not** nested
      
   some code

      
   ... and this is also shown left-aligned when it shouldn't, so it's not a matter of nesting.

5. Bla bla

   This works fine.

GitHub gets this right (except the numbering), MarkAPL doesn't.