Merged revision(s) 1525246 from lucene/dev/trunk:
SOLR-4882: Restrict SolrResourceLoader to only allow access to resource files below the instance dir

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1525248 13f79535-47bb-0310-9956-ffa450edef68