Clean up Pathfinder.

* Restrict to 80-columns and other style cleanups.
* Make pathfinding a free function and hide the class Pathfinder.
* Split off unrelated utility functions into separate files.

Conflicts:
	src/ripple/rpc/handlers/RipplePathFind.cpp

src/ripple/app/main/Application.cpp

@@ -25,6 +25,7 @@
 #include <ripple/basics/Sustain.h>
 #include <ripple/common/seconds_clock.h>
 #include <ripple/common/make_SSLContext.h>
+#include <ripple/app/paths/FindPaths.h>
 #include <ripple/core/LoadFeeTrack.h>
 #include <ripple/nodestore/Database.h>
 #include <ripple/nodestore/DummyScheduler.h>
@@ -644,7 +645,7 @@ public:
             updateTables ();
 
         m_amendmentTable->addInitial();
-        Pathfinder::initPathTable ();
+        initializePathfinding ();
 
         m_ledgerMaster->setMinValidations (getConfig ().VALIDATION_QUORUM);