Feature/sample UI wallet dropdown (#38)

* Created WalletDropdown. Open and close WalletDropdown page

* Add functionality to WalletDropdown. Require an address when opening WalletPanel - use this to populate the top bar. Add UI tests for WalletDropdown and topbar wallet address

* Fix comment

* Fixed a bug which messed with WalletPanel navigation if you clicked on a button on a page that isn't the WalletDropdown while the WalletDropdown is open. Added UI tests to confirm the bug doesn't return as a regression

* Fix ColorSchemeManager

Assets/SequenceExamples/Prefabs/SearchElement.prefab

@@ -504,7 +504,7 @@ MonoBehaviour:
   m_fontColor32:
     serializedVersion: 2
     rgba: 4281479730
-  m_fontColor: {r: 0.19607843, g: 0.19607843, b: 0.19607843, a: 1}
+  m_fontColor: {r: 0, g: 0, b: 0, a: 1}
   m_enableVertexGradient: 0
   m_colorMode: 3
   m_fontColorGradient:

Assets/SequenceExamples/Prefabs/Token.prefab

@@ -703,7 +703,7 @@ MonoBehaviour:
   m_Name: 
   m_EditorClassIdentifier: 
   m_Material: {fileID: 0}
-  m_Color: {r: 1, g: 1, b: 1, a: 0.5686275}
+  m_Color: {r: 1, g: 1, b: 1, a: 1}
   m_RaycastTarget: 1
   m_RaycastPadding: {x: 0, y: 0, z: 0, w: 0}
   m_Maskable: 1