Improvement: Hash-keyed Try-It-Out parameter value storage (#4670)

* allow param update by identity + hashed value storage

* add specActions.changeParamByIdentity

* add identity-based lookup support in spec selectors

* migrate `changeParam` usage to `changeParamByIdentity`

* migrate usage of `parameterWithMeta` to `parameterWithMetaByIdentity`

* update invocations of `changeParamByIdentity` to match fn signature

* use OrderedMap throughout hash-based selectors for consistency

* normalize usage of ParameterRow `onChange`

* migrate bug 4557 tests to reflect new ParameterRow interface

* remove exclusive test blocks

* linter fixes

* copy Parameters changes into OAS3 wrapper

* use rawParam for meta lookups in ParameterRow

src/core/plugins/spec/actions.js

@@ -234,6 +234,13 @@ export function changeParam( path, paramName, paramIn, value, isXml ){
   }
 }
 
+export function changeParamByIdentity( pathMethod, param, value, isXml ){
+  return {
+    type: UPDATE_PARAM,
+    payload:{ path: pathMethod, param, value, isXml }
+  }
+}
+
 export const updateResolvedSubtree = (path, value) => {
   return {
     type: UPDATE_RESOLVED_SUBTREE,