add xa transaction for sharing-proxy

[cherrylzhao]

target：

1. client can swith none/xa/tcc transaction by yaml file.
2. based on atomikos to implement xa transaction.
3. proxy server provide transaction manager based on netty-channel，sql instructions would execute through 2PC protocol.

prerequisite

1. don't support transaction/non-transaction exist at same time within one long connection.
2. DDL instruction don't support global transaction.

[terrymanu]

fixed at 3.0.0.M3