SOLR-4839: Re-organized upgrade notes and added notes about removing the ability to run java -jar start.jar directly and removal of SOLR_SSL_PORT property.
SOLR-4839: Re-organized upgrade notes and added notes about removing the ability to run java -jar start.jar directly and removal of SOLR_SSL_PORT property.

git-svn-id: 308d55f399f3bd9aa0560a10e81a003040006c48@1676116 13f79535-47bb-0310-9956-ffa450edef68

apache/solr,apache/solr,apache/solr,apache/solr,apache/solr