SOLR-6435: Add script to simplify posting content to Solr

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1647928 13f79535-47bb-0310-9956-ffa450edef68
Add a couple of recent change mentions, to the trunk/6.0 section but these will ideally be committed to branch_5x eventually too

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1647929 13f79535-47bb-0310-9956-ffa450edef68
Adjust films README using new bin/post script instead of curl

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1647930 13f79535-47bb-0310-9956-ffa450edef68