create a new service to activate RA with method activate(ra.xml, ironjacamar.xml, classloader)

the method will get the necessary metadata representation and the classloader and will activate a ra. The necessary java code for ra is not deployed but it's cosidered already loaded by the given classloader.
Consider also a variant taking ra.xml and ij.xml as string containing the xml and proved parse too. Anyway the priority is on metadata variant