AG-420 Improve React implementation

src-trader-dashboard/reducers/fxDataReducer.jsx

@@ -0,0 +1,16 @@
+export default (state = {fxData: [], fxTopMovers: []}, action) => {
+    switch (action.type) {
+        case 'FX_DATA_CHANGED':
+            return {
+                ...state,
+                fxData: action.fxData.slice(0),
+            };
+        case 'FX_TOP_MOVERS_CHANGED':
+            return {
+                ...state,
+                fxTopMovers: action.fxTopMovers.slice(0),
+            };
+        default:
+            return action.state;
+    }
+};