Issues with empty dicts and lists
Starting with an empty dict or list then adding to them generates compiler asserts or errors.  Here is a simple program showing the issues.

```nim
import json

var myList = %* []
echo myList

var myTable = %* {}
echo myTable # expect {} not []

var myTable2 = %*
  {}
echo myTable2 # expect {} not []

# Error: type mismatch: got (JsonNode) but expected 'JsonNodeObj = object'
# myList[] = %* 5
# echo myList

# Compiler assert
#myTable["hi"] =  %* 42
#echo myTable

# This way works.
var table3 = parseJson("{}")
echo pretty(table3)

table3["hi"] = %* 42
echo table3

table3["meta"] = %* {"filename": "image.dng", "size": 55}
echo table3
```