Partially solving issue 1788: "Crashing during processing of queue"

It also correct a bug of wrong image orientation (was wrong in the File Browser while good in the Editor tab)

This patch also introduce several speed optimizations like:
   - switch between File Browser and Editor tab in Single Editor mode
   - asynchronous computation of the Batch Queue's thumbnails
   - quick start of RT even with a huge queue
   - less GUI overhead when applying a profile to multiple thumbs in the File Browser

rtgui/batchtoolpanelcoord.h

@@ -30,6 +30,7 @@ class FilePanel;
 class BatchToolPanelCoordinator : 
                                 public ToolPanelCoordinator, 
                                 public FileSelectionChangeListener,
+                                public BatchPParamsChangeListener,
                                 public ThumbnailListener
 {
     protected:
@@ -39,6 +40,7 @@ class BatchToolPanelCoordinator :
         std::vector<Glib::ustring> selFileNames;
         std::vector<rtengine::procparams::ProcParams> initialPP;
         bool somethingChanged;
+        bool blockedUpdate;
         FilePanel* parent;
 
         void closeSession (bool save=true);
@@ -63,7 +65,11 @@ class BatchToolPanelCoordinator :
 
         // thumbnaillistener interface
         void procParamsChanged (Thumbnail* thm, int whoChangedIt);
-        
+
+        // batchpparamschangelistener interface
+        void beginBatchPParamsChange(int numberOfEntries);
+        void endBatchPParamsChange();
+
         // imageareatoollistener interface
         void spotWBselected (int x, int y, Thumbnail* thm=NULL);
         void cropSelectionReady ();