pom.xml: updates for release 0.90
pom.xml: updates for release 0.90

Add missing slf4j SimpleLogger for testng tests to make sure we print the date of each log line

Signed-off-by: stephane brossier <c1fb28815da1df8a6921017a648d6c4b5d859b78@groupon.com>

killbill/killbill-oss-parent