Add support to JSON literals, configure property nesting, original sections inclusion and array literal parsing behaviour

I've added support for enable/disable property nesting, set the behaviour of the array literals (parse json / parse simple arrays / no parse at all) and another useful option to clean up the final array by removing the original pre-inherited sections. Also, the final output order now respect the original sections order. And some bugs are fixed (they're explained in the commits).

This description for JSON literals can be incluided in the README:

Dictionaries and complex structures

Besides arrays, you can create dictionaries and more complex structures using JSON syntax. For example, you can use:

     staff = '{
        "boss": {
           "name": "John", 
           "age": 42 
        }, 
        "staff": [
           {
              "name": "Mark" 
              "age": 35 
           }, 
           {
              "name": "Bill" 
              "age": 44 
           } 
        ] 
     } '

NOTE: Remember to wrap the JSON strings in single quotes for a correct analysis. The JSON names must be enclosed in double quotes and trailing commas are not allowed.