* Recycle EntryImpl of EntryCache

* remove position import from Entry

* Use proper ref-counting semantic for Entry and removed position-impl recycling

* release data after retain into Entry + make variables final in position

* Fixed ref-counting after reading entries

* Introduce new load manager API

* Fix formatting and style issues

* Fix imports

* Add back renamed classes

* Add policies to ModularLoadManagerImpl

* Make system resource usage more influential

* Fix reflective setting of load manager in tests

* Conform with mockito syntax

* Improve formatting and design

* Revert to old simulation behavior, use reflective interface design

* Remove unnecessary async call

* Fix formatting

* Remove git merge remnant

* Refactor some classes and put loadManagerClassName in dynamic conf

* Delete LoadSimulationServer

* Clean API, share more code

* Remove redundant synchronized block, make correction to onUpdate

* Fix policy filter bug

* Remove availableActiveBrokers.get() call

* Use connection pooling

* Remove unused code

* Don't try reading the symlink and converting to absolute path

* Remove redundant and unnecessary statments

* Add test back to see if path contains /virtual/

* Replace System.out statements with log.info

* Change %s to {}

Changes includes:
  * Fixes for 64bit ledger ids
  * Fixed memory leak on read-only bookies
  * Fixed datasketches metric provider concurrency issue

* translate documents into japanese

* reference the same files under doc/images folder

* fixed typo

* delete unnecessary line

* Change the expression of a few words

* add a link to the translation in Documentation.md

reduce collection instances while generating metrics

PR from @sschepens  + tests and few fixes from @merlimat