Weld thread pool should be wildfly global

Weld keeps a thread pool for each deployment.
Per default the pool is filled with "numProcessors" threads (see http://docs.jboss.org/weld/reference/latest/en-US/html/configure.html)
When having many deployments, a single thread pool for the wildfly instance could improve the overall performance.
This thread pool should be configurable in the weld subsystem of the wildfly configuration (e.g. standalone.xml).