LUCENE-4763: Fix Java version detection in common-build.xml, use correct source version for javadocs, fail build on unsupported java version when documentation linting is enabled
LUCENE-4763: Fix Java version detection in common-build.xml, use correct source version for javadocs, fail build on unsupported java version when documentation linting is enabled

git-svn-id: 308d55f399f3bd9aa0560a10e81a003040006c48@1444254 13f79535-47bb-0310-9956-ffa450edef68

cscorley/solr-only-mirror,cscorley/solr-only-mirror,cscorley/solr-only-mirror