pom.xml: update killbill-oss-parent to 0.4.3

The main changes are around lifecycle of metrics and new configuration
in the killbill-commons queues.

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
Merge branch 'master' of github.com:killbill/killbill

Conflicts:
	pom.xml
	server/src/test/java/com/ning/billing/jaxrs/TestJaxrsBase.java

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>