Refactor View, MetaView, and tx processing:

This tidies up the View interface and makes transaction
application a free function, with the removal of the
TransactionEngine class. A new class ApplyContext provides
all the state information needed to apply a Transactor. The
Transactor is refactored to perform all the processing
activities previously part of TransactionEngine.

The calculation of metadata from a MetaView is improved.
A new apply function performs all the steps for calculating
and inserting metadata into the tx map.

Transaction processing code path is passed a Config instead
of retrieving the global, and uses the Journal supplied in
the call to apply() consistently.

To support transaction processing and RPC operations, a
new POD type ViewInfo is added which consolidates static
information about open and closed ledgers, such as the ledger
sequence number or the closing times. Ledger and MetaView are
refactored to use this info.

The ViewInfo now contains the "open ledger" setting. The
tapOPEN_LEDGER ViewFlag is removed. The view property of
being an open ledger is obtained from the base or by using
the MetaView constructor which presents a closed ledger as
an open one.

View, MetaView:

* Fix missing includes
* Add apply free function
* Use Journal in TransactionEngine
* Use BasicView in TransactionEngine
* inline NetworkOPs::batchApply
* Add shallow_copy, open_ledger MetaView ctor tags
* Add ViewInfo with open flag, seq, close times
* Make parent_ a reference
* Tidy up ctor arguments and base_ name
* Remove tapOPEN_LEDGER
* add assert to MetaView::apply
* ViewInfo comment
* Throw, pass Journal in txInsert
* Add BasicView::txCount

TransactionEngine:

* Add apply
* Make TransactionEngine private
* Refactor MetaView::apply and apply()
* Rename to TxMeta
* Refactor treatment of metadata in MetaView, TransactionEngine
* Rename to ApplyContext
* Use ApplyContext& in Transactor
* Pass Config in ApplyContext
* Declare Transactor classes in headers
* Use view flags in Transactor

src/ripple/app/tx/impl/apply.cpp

@@ -0,0 +1,86 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012, 2013 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include <BeastConfig.h>
+#include <ripple/app/tx/apply.h>
+#include <ripple/app/tx/impl/ApplyContext.h>
+
+#include <ripple/app/tx/impl/CancelOffer.h>
+#include <ripple/app/tx/impl/CancelTicket.h>
+#include <ripple/app/tx/impl/Change.h>
+#include <ripple/app/tx/impl/CreateOffer.h>
+#include <ripple/app/tx/impl/CreateTicket.h>
+#include <ripple/app/tx/impl/Payment.h>
+#include <ripple/app/tx/impl/SetAccount.h>
+#include <ripple/app/tx/impl/SetRegularKey.h>
+#include <ripple/app/tx/impl/SetSignerList.h>
+#include <ripple/app/tx/impl/SetTrust.h>
+
+namespace ripple {
+
+template <class Processor,
+    class... Args>
+static
+std::pair<TER, bool>
+do_apply (Args&&... args)
+{
+    ApplyContext ctx (
+        std::forward<Args>(args)...);
+    Processor p(ctx);
+    return p();
+}
+
+template <class... Args>
+static
+std::pair<TER, bool>
+invoke (TxType type,
+    Args&&... args)
+{
+    switch(type)
+    {
+    case ttACCOUNT_SET:     return do_apply< SetAccount    >(std::forward<Args>(args)...);
+    case ttOFFER_CANCEL:    return do_apply< CancelOffer   >(std::forward<Args>(args)...);
+    case ttOFFER_CREATE:    return do_apply< CreateOffer   >(std::forward<Args>(args)...);
+    case ttPAYMENT:         return do_apply< Payment       >(std::forward<Args>(args)...);
+    case ttREGULAR_KEY_SET: return do_apply< SetRegularKey >(std::forward<Args>(args)...);
+    case ttSIGNER_LIST_SET: return do_apply< SetSignerList >(std::forward<Args>(args)...);
+    case ttTICKET_CANCEL:   return do_apply< CancelTicket  >(std::forward<Args>(args)...);
+    case ttTICKET_CREATE:   return do_apply< CreateTicket  >(std::forward<Args>(args)...);
+    case ttTRUST_SET:       return do_apply< SetTrust      >(std::forward<Args>(args)...);
+
+    // VFALCO These are both the same?
+    case ttAMENDMENT:
+    case ttFEE:             return do_apply< Change        >(std::forward<Args>(args)...);
+    default:
+        break;
+    }
+    return { temUNKNOWN, false };
+}
+
+std::pair<TER, bool>
+apply (BasicView& view,
+    STTx const& tx, ViewFlags flags,
+        Config const& config,
+            beast::Journal journal)
+{
+    return invoke (tx.getTxnType(),
+        view, tx, flags, config, journal);
+}
+
+} // ripple