Update DataSource auto-configuration to support XA

Update DataSource and JPA auto-configuration to consider XA datasources.

See gh-947
Update JMS auto-configuration to support XA

Update JMS auto-configuration for ActiveMQ and HornetQ to support XA
transactions.

See gh-947
Add Atomikos and Bitronix starter POMs

Add starters for Atomikos and Bitronix JTA libraries.

See gh-947
Add Atomikos and Bitronix JTA samples

Add samples and integration tests for Atomikos and Bitronix JTA.

See gh-947