core: Add support for annotation indexes

This change modifies the maven plugin that generates JBoss modules so
that it creates annotation indexes. For each .jar file inside the module
a new META-INF/jandex.idx resource will be added.

These annotations index speeds up the deployment of the applications and
are required in order to allow scanning of annotations from other
modules, otherwise they are silently ignored.

Change-Id: I3556fc385efc2ae138d2ad12b7d9d467bb5fff67
Related: https://bugzilla.redhat.com/1113485
Signed-off-by: Juan Hernandez <juan.hernandez@redhat.com>