Add a flag to print out statistics for both system dictionary and shared dictionary

Currently if we want to print out shared dictionary, we have to use -XX:+PrintSharedArchiveAndExit and -XX:+PrintSharedDictionary, and this is only for shared dictinoary (this also include list of java classes in the output). If want to print out dictionary, we need PrintSystemDictionaryAtExit which is a debug flag and only at exit print out the data. Users will be confused with them.

We cannot get SystemDictionary statistic data by using those flags, also, cannot get system dictionary and shared dictionary info at same time! You have to run with flags separately.

We need a flag to print out statistics for both dictionary and shared dictionary (PrintSystemDictionaryStatistics). Not only at exit, but can be retrieved by jcmd. Also reorg the flags or redesign those flags to have a clean definition.