* Compute the effective recipient.
* Make sure the effective recipient exists.
* Prohibit paths to the recipient, if not the effective recipient.
* Treat paths to the effective recipient as complete.
* Don't find looped paths.
* Use the effective recipient for getPathsOut weight.
An alternative to the unity build, the classic build compiles each
translation unit individually. This adds more modules to the classic build:
* Remove unity header app.h
* Add missing includes as needed
* Remove obsolete NodeStore backend code
* Add app/, core/, crypto/, json/, net/, overlay/, peerfinder/ to classic build
* Allow pathfinding requests where the starting currency may have
multiple issuers.
* Cache paths over all issuers to avoid repeating work.
* Clear the ledger checkpoint in one retry case.
* Add an additional node at the front of paths when the starting issuer
is not the source account.
* 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
