Feature - merge command

- Merged patch that implements the first milestone of the merge
  feature.  Thanks to Johannes Schlatow.

src/Taskmod.h

@@ -0,0 +1,77 @@
+////////////////////////////////////////////////////////////////////////////////
+// task - a command line task list manager.
+//
+// Copyright 2006 - 2010, Paul Beckingham.
+// All rights reserved.
+//
+// This program is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free Software
+// Foundation; either version 2 of the License, or (at your option) any later
+// version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+// details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program; if not, write to the
+//
+//     Free Software Foundation, Inc.,
+//     51 Franklin Street, Fifth Floor,
+//     Boston, MA
+//     02110-1301
+//     USA
+//
+////////////////////////////////////////////////////////////////////////////////
+#ifndef INCLUDED_TASKMOD
+#define INCLUDED_TASKMOD
+
+#include <string>
+#include <Task.h>
+
+class Taskmod {
+
+public:
+  Taskmod();
+  Taskmod(const Taskmod& other);
+  ~Taskmod();
+
+  // operators
+  bool operator< (const Taskmod& compare);
+  bool operator> (const Taskmod& compare);
+  bool operator== (const Taskmod& compare);
+  bool operator!= (const Taskmod& compare);
+  Taskmod& operator= (const Taskmod& other);
+
+  // helper
+  void reset(long timestamp=0);
+  bool isNew();
+  bool issetBefore();
+  bool issetAfter();
+  bool isValid();
+
+  std::string getUuid();
+  std::string toString();
+
+  // setter
+  void setAfter(const Task& after);
+  void setBefore(const Task& before);
+  void setTimestamp(long timestamp);
+
+  // getter
+  Task& getAfter();
+  Task& getBefore();
+  long getTimestamp() const;
+  std::string getTimeStr() const;
+
+protected:
+  Task after;
+  Task before;
+  long timestamp;
+  bool bAfterSet;
+  bool bBeforeSet;
+};
+
+#endif
+