LazyflowSource: Don't create lazyflow requests lazily.
(lazyflow requests are no longer auto-submitted upon construction, so delayed construction is not necessary.)
VolumeRendering: Transpose volume data for both read and write.
layerstack: Added moveToSelectedToRow()
ShortcutManager: Instead of warning the user about duplicate shortcuts, simply disable conflicting shortcuts.
Newly registered shortcuts take precedence over previously registered shortcuts.
BrusingController: Don't draw a brush stroke if the user double-clicks.
(Handle single clicks via a QTimer that is cancelled by double-clicks.)
LayerWidget: Draw alternating row background colors.
tiling: 'direct' layers are not 'direct' for prefetching requests.
Navigation Controller: Scroll N slices at a time depending on the speed of the scrool wheel.
ShortcutManagerDlg: When changing a shortcut key conflicts with an existing key, just clear the conflicting shortcut.
LazyflowSource: Replaced Op5ifyer with OpReorderAxes (same thing, but slightly faster/cleaner implementation).