Remove FeeVote.h from app.h
Remove STTx.h from app.h
Remove IHashRouter.h from app.h
Remove AmendmentTable.h from app.h
Remove STLedgerEntry.h from app.h
Remove LedgerEntrySet.h from app.h
Remove AcceptedLedger.h from app.h
Remove AcceptedLedgerTx.h from app.h