UDA Edit

- Added UDA and Orphan support to the 'edit' command.  It will show the
  data, but not yet recognize changes to that data.

src/commands/CmdEdit.h

@@ -42,6 +42,7 @@ public:
 private:
   std::string findValue (const std::string&, const std::string&);
   std::string formatDate (Task&, const std::string&, const std::string&);
+  std::string formatDuration (Task&, const std::string&);
   std::string formatTask (Task, const std::string&);
   void parseTask (Task&, const std::string&, const std::string&);
   bool editFile (Task&);