General refactoring, using C++11

* Remove broken RecycledObjectPool

* Fix beast::ServiceQueue using List instead of LockFreeStack

* Add class semaphore, fixes broken Semaphore

* Move crytpo module files to new beast directory

* Use c++11 replacements for boost and beast types:
  - std::atomic instead of beast::Atomic
  - std::function instead of boost::function, beast::function
  - std::unique_ptr instead of beast::ScopedPointer
  - std::shared_ptr instead of boost::shared_ptr

* Remove modules:
  - beast_db
  - beast_crypto
  - beast_extras

* Remove unnecessary classes:
  - AbstractFifo
  - AddConst
  - AtomicCounter
  - AtomicFlag
  - AtomicPointer
  - AtomicState
  - CopyConst
  - Expression
  - ForwardList
  - IfCond
  - Interval
  - IntrusiveArray
  - KeyvaDB
  - PointerToOther
  - PointerTraits
  - RemoveConst
  - RemoveConstVolatile
  - RemoveReference
  - RemoveVolatile
  - SharedObjectArray
  - SingleThreadedSharedObject
  - SophiaDB factory
  - SortedSet
  - WeakReference
  - beast::unique_ptr

src/ripple_app/ledger/LedgerEntrySet.cpp

@@ -213,7 +213,8 @@ void LedgerEntrySet::entryModify (SLE::ref sle)
     {
     case taaCACHED:
         it->second.mAction  = taaMODIFY;
-        fallthru ();
+        
+        // Fall through
 
     case taaCREATE:
     case taaMODIFY:
@@ -641,7 +642,7 @@ TER LedgerEntrySet::dirAdd (
     uint64&                                 uNodeDir,
     uint256 const&                          uRootIndex,
     uint256 const&                          uLedgerIndex,
-    FUNCTION_TYPE<void (SLE::ref, bool)>    fDescriber)
+    std::function<void (SLE::ref, bool)>    fDescriber)
 {
     WriteLog (lsTRACE, LedgerEntrySet) << boost::str (boost::format ("dirAdd: uRootIndex=%s uLedgerIndex=%s")
                                        % uRootIndex.ToString ()