upgrade to log4j-2.0-rc2-SNAPSHOT

Changes required to build against the next version of log4j2 "2.0-rc2".

Again it's worth adding "?w=1" to the url to avoid the whitespace changes.
 (maybe it's worth making it a project standard not to add trailing whitespace?)


I did this work in correspondence with https://issues.apache.org/jira/browse/LOG4J2-673