SOLR-5463: move CHANGES to 4.7 for backporting

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1557192 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5529: add support for queries to use multiple suggesters in SuggestComponent

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1557206 13f79535-47bb-0310-9956-ffa450edef68