Revert "Util constructor protected"

This reverts commit 24ebb9bd7e725b7aee9b951caa0b6049dfce0fc8.
Revert "Using Util as a singleton to override base64 encoder"

This reverts commit 17a20fb3d6f32369b21e53986e15974d1df7d225.
Using third party Base64 encoder