[processing] Give an option for all file types to be used as input layer to processing algorithms.

python/plugins/processing/gui/InputLayerSelectorPanel.py

@@ -63,7 +63,7 @@ class InputLayerSelectorPanel(QtGui.QWidget):
             path = ''
 
         filename = QtGui.QFileDialog.getOpenFileName(self, self.param.description, path,
-                self.param.getFileFilter())
+                'All files(*.*);;' + self.param.getFileFilter())
         if filename:
             self.text.addItem(filename, filename)
             self.text.setCurrentIndex(self.text.count() - 1)