Vectorscope changes:

Vectorscope changes:
* Magnification = Gain can now be changed with a slider in 0.1 steps up to 4x
* Vectorscope generator extracted to separate (re-usable) class
* Inherits from AbstractScopeWidget, which means
  - Lots of duplicate code removed
  - Realtime bug that led to crash fixed (I hope)
* Checks whether events have been connected successfully with Q_ASSERT
* Delete members in the destructor
* .ui file: Palette removed, unnecessary grid layout removed as well
AbstractScopeWidget changes:
* Processing HUD and Background as well now.
* Re-render when auto refresh is selected
* Don't recalculate if the scope is hidden behind another widget
* Slot added to force the update of a certain layer
* Update scope when risen to top of a widget stack
* Realtime acceleration factor can now be calculated by the implementing widget
* Acceleration factor is protected instead of private now so that they can be accessed by other render tasks (hud displays scope factor e.g.)
WaveformGenerator changes:
* Using subclassing instead of direct #includes in the .h file («good style» :P)

svn path=/trunk/kdenlive/; revision=4611