Use a better mechanism to parse config files

The current codebase heavily relies on JAXB to:

1. Generate a XSD schema from a Configuration bean
2. Generate a parser to use with an XML configuration

This is known to be slow, and can significantly add to start up time:

We did some analysis of our AS6 descriptor code which was using JAXB (800ms), compared to straight stax (10ms)

A possible solution could be to still use JAXB to generate the schema, but to also write a Maven plugin which would generate a STAX parser based on the XSD schema and Configuration bean at build time. Infinispan would then use this STAX parser rather than a JAXB generated parser, which would be a lot faster.