Update the root README.md
Merge pull request #7029 from Sanne/ReadmeUpdated

Update the root README.md
bump wildfly-core to 1.0.0.Alpha15-SNAPSHOT
add XML validation for bean-validation subsystem
add XML validation for batch subsystem
add XML validation for connector subsystems
add XML validation for ee subsystem

modify the XSD to put the concurrent children in the order persisted
by the subsystem
add XML validation for ejb3 subsystem
add XML validation for jacorb subsystem
add XML validation for jaxrs subsystem
add XML validation for jdr subsystem
add XML validation for jpa subsystem
add XML validation for jsf subsystem
add XML validation for jsr77 subsystem
add XML validation for mail subsystem
add XML validation to messaging subsystem
add XML validation for mod_cluster subsystem

FIXME: the ssl's protocol attribute has a default value of TLS that is
not valid for the XSD SSlProtocolType type.
add XML validation for naming subsystem
add XML validation for picketlink subsystems
add XML validation for rts subsystem