SOLR-4952: make TestConfig use solrconfig.snippet.randomindexconfig.xml - this involved moving some 'default' tests arround, prunning down solrconfig-termindex.xml, and renaming solrconfig-termindex.xml -> solrconfig-test-misc.xml since the mane 'termindex' made no sense for what it is used for

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1513312 13f79535-47bb-0310-9956-ffa450edef68