New types Account, Currency, Directory:

* New tagged uint types.
* Extract to_string functions from header to hide dependencies.
* Include what you use and C++11 for cleanups.

src/ripple/module/rpc/impl/TransactionSign.cpp

@@ -122,8 +122,8 @@ static Json::Value signPayment(
     {
         // Need a ripple path.
         STPathSet   spsPaths;
-        uint160     uSrcCurrencyID;
-        uint160     uSrcIssuerID;
+        Currency uSrcCurrencyID;
+        Account uSrcIssuerID;
 
         STAmount    saSendMax;