MySQL BIGINT UNSIGNED / Java BigInteger codec

[jinwik]

Motivation:

https://github.com/mysql/mysql-connector-j/blob/release/8.x/src/main/user-impl/java/com/mysql/cj/jdbc/result/ResultSetImpl.java#L1153

Explain here the context, and why you're making that change, what is the problem you're trying to solve.

Conformance:

You should have signed the Eclipse Contributor Agreement as explained in https://github.com/eclipse/vert.x/blob/master/CONTRIBUTING.md Please also make sure you adhere to the code style guidelines: https://github.com/vert-x3/wiki/wiki/Vert.x-code-style-guidelines

[tsegismont]

From a quick look, it's fine with me, wdyt @BillyYccc ?

We'd need a test case for encoding as well