Add support for query params (#22)

Issue: #20

Author: ssutar

transforms/ember-object/__testfixtures__/basic.input.js

@@ -9,6 +9,7 @@ const Foo = Test.extend(MyMixin, {
   boolProp: true,
   numProp: 123,
   [MY_VAL]: "val",
+  queryParams: {},
 
   /**
    * Method comments

transforms/ember-object/__testfixtures__/basic.output.js

@@ -10,6 +10,7 @@ class Foo extends Test.extend(MyMixin) {
   boolProp = true;
   numProp = 123;
   [MY_VAL] = "val";
+  queryParams = {};
 
   /**
    * Method comments

transforms/helpers/validation-helper.js

@@ -40,7 +40,7 @@ function hasValidProps(
       unsupportedPropNames.includes(instanceProp.name) ||
       (!classFields && instanceProp.type === "Literal") ||
       (instanceProp.type === "ObjectExpression" &&
-        instanceProp.name !== "actions") ||
+        !["actions", "queryParams"].includes(instanceProp.name)) ||
       (instanceProp.isCallExpression && !instanceProp.hasDecorators)
     ) {
       return false;