The Stoppable interface aids in the enforcement of invariants needed to
successful start and stop a multi-threaded application composed of classes
that depend on each other in complex ways.
* Test written to confirm the current behavior.
* Comments updated to reflect the current behavior.
* Public API reduced to what is currently in use.
* Protected data members made private.
* volatile bool members changed to std::atomic<bool>.
* std::atomic<int> members changed to std::atomic<bool>.
* Name storage uses std::string
Beast includes a lot of code for encapsulating cross-platform differences
which are not used or needed by rippled. Additionally, a lot of that code
implements functionality that is available from the standard library.
This moves away from custom implementations of features that the standard
library provides and reduces the number of platform-specific interfaces
andfeatures that Beast makes available.
Highlights include:
* Use std:: instead of beast implementations when possible
* Reduce the use of beast::String in public interfaces
* Remove Windows-specific COM and Registry code
* Reduce the public interface of beast::File
* Reduce the public interface of beast::SystemStats
* Remove unused sysctl/getsysinfo functions
* Remove beast::Logger
