Optimize redundant double reference for Group elements

[ccromjongh]

Currently the JSON output gives renders group elements as references that refer to references to the actual type. This is superfluous, and the first reference could be directly replaced with the second one.

Example now:

"logic_group_generated_119_218_L7n3uhlP_1__b": {
  "type": "Ref",
  "value": "package_pack0__generated_0_6_AXTfYq6d_5"
},
"logic_group_generated_119_218_L7n3uhlP_1__g": {
  "type": "Ref",
  "value": "package_pack0__generated_0_6_AXTfYq6d_5"
},
"logic_group_generated_119_218_L7n3uhlP_1__r": {
  "type": "Ref",
  "value": "package_pack0__generated_0_6_IJOt1EjR_7"
},
"package_pack0__generated_0_6_AXTfYq6d_5": {
  "type": "Bit",
  "value": 8
},
"package_pack0__generated_0_6_IJOt1EjR_7": {
  "type": "Bit",
  "value": 8
},
"package_pack0__rgb": {
  "type": "Group",
  "value": {
    "elements": {
      "b": {
        "type": "Ref",
        "value": "logic_group_generated_119_218_L7n3uhlP_1__b"
      },
      "g": {
        "type": "Ref",
        "value": "logic_group_generated_119_218_L7n3uhlP_1__g"
      },
      "r": {
        "type": "Ref",
        "value": "logic_group_generated_119_218_L7n3uhlP_1__r"
      }
    }
  }
}

Envisioned:

"package_pack0__generated_0_6_AXTfYq6d_5": {
  "type": "Bit",
  "value": 8
},
"package_pack0__generated_0_6_IJOt1EjR_7": {
  "type": "Bit",
  "value": 8
},
"package_pack0__rgb": {
  "type": "Group",
  "value": {
    "elements": {
      "b": {
        "type": "Ref",
        "value": "package_pack0__generated_0_6_AXTfYq6d_5"
      },
      "g": {
        "type": "Ref",
        "value": "package_pack0__generated_0_6_AXTfYq6d_5"
      },
      "r": {
        "type": "Ref",
        "value": "package_pack0__generated_0_6_IJOt1EjR_7"
      }
    }
  }
}