The SHAMap class is refactored into a separate module where each translation
unit compiles separate without errors. Dependencies on higher level business
logic are removed. SHAMap now depends only on basics, crypto, nodestore,
and protocol:
* Inject NodeStore::Database& to SHAMap
* Move sync filter instances to app/ledger/
* Move shamap to its own module
* Move FullBelowCache to shamap/
* Move private code to shamap/impl/
* Refactor SHAMap treatment of missing node handler
* Inject and use Journal for logging in SHAMap
* Added new test APIs allowing easy ways to create ledgers, apply
transactions to them, close and advance them.
* Moved Ledger tests from Ledger.cpp to Ledger.test.cpp.
* Changed several TransactionEngine log priorities from lsINFO to lsDEBUG to
reduce unnecessary verbosity in the log messages while running these tests.
* Moved LedgerConsensus:applyTransactions from a private member function to a
free function so that it could be accessed externally, and without having to
reference a LedgerConsensus object. This was done to facilitate the new
testing API.
* Remove AccountItems and AccountItem
* Restructure RippleLineCache to not require shared_ptr
* Avoid expensive copies of base_uint<160> in RippleState
* Rename unity files
* Move some modules to new subdirectories
* Remove obsolete Visual Studio project files
* Remove obsolete coding style and TODO list
