Lyubomir Ivanov

Sure, make a PR and I would thankfully merge it.

@martinheidegger These two had been implemented. ``` crypto_scalarmult_base crypto_scalarmult ```

Thank you for your PR. Can you please explain in more detail, some concrete use cases of these utility functions as they are not related to sodium library.

@dan714 What's the reason of changing minSdkVersion to 21?