Implement URLExecute() function

[axkr]

Implement a function URLExecute(url-as-string) which returns the reponse of a http query as JSON format from a Rest API and returns a List() of nested Lists of Rules representing the JSON format.

Take for example the wikipedia api:

• http://en.wikipedia.org/w/api.php

which can return a response in json or jsonfm format

• https://en.wikipedia.org/w/api.php?action=query&list=search&srsearch=Leonhard%20Euler&format=json
• https://en.wikipedia.org/w/api.php?action=query&list=search&srsearch=Leonhard%20Euler&format=jsonfm

In FullForm format the list will have a structure like this:

List( 
  Rule("tag1", 1234), 
  Rule("tag2", List(
                        Rule("subTag1",42),...)
  )
)