Added SelfServe UI updates (#559)

* Added SelfServe UI modifications

* fixed lint error

* addressed PR comments

src/SelfServe/SelfServeStyles.tsx

@@ -0,0 +1,20 @@
+import { IButtonStyles, ICommandBarStyles, ISeparatorStyles, IStackTokens } from "office-ui-fabric-react";
+import { StyleConstants } from "../Common/Constants";
+
+export const commandBarItemStyles: IButtonStyles = { root: { paddingLeft: 20 } };
+
+export const commandBarStyles: ICommandBarStyles = { root: { paddingLeft: 0 } };
+
+export const containerStackTokens: IStackTokens = { childrenGap: 5, padding: 10 };
+
+export const separatorStyles: Partial<ISeparatorStyles> = {
+  root: {
+    selectors: {
+      "::before": {
+        background: StyleConstants.BaseMedium,
+      },
+    },
+    padding: 0,
+    height: 1,
+  },
+};