Improved support for maps

[Umaaz]

Is your feature request related to a problem? Please describe.
Currently if a map is collected the key is always converted to a string, meaning that complex keys do not work.

Describe the solution you'd like
Wrap the key entries in a deep.MapEntry type. This allows the UI to treat all maps from all languages the same. This type should then define child variables as:

{
 type: 'deep.MapEntry',
 value: '0',
 hash: '123.0',
 children: [
    {
      id: '124',
      name: 'key'
    }
    {
      id: '125',
      name: 'value'
    }
  ]
}

Describe alternatives you've considered
Add explicitly the fields for map entries.

Additional context
Look at how NV handled this.