[Kst] extragear/graphics/kst/src/plugins

[Brisset, Nicolas]

I'd like to mention just one thing here: I had left it out of the
official build as it currently lacks frequency pre-warping. Not
necessarily a big deal (and difficult to make it work in the general
case anyway) but good to keep in mind.
The initialization is also a bit basic. I'll try to improve that...

> SVN commit 611354 by treat:
> 
> * Convert generic filter plugin and get rid of hand written 
> makefile. Integrate into build.
> 
> 
>  M  +1 -1      Makefile.am  
>  D             discretizing_filters/Makefile  
>  A             discretizing_filters/Makefile.am  
>  A             discretizing_filters/genericfilter.cpp   
> [License: GPL (v2+)]
>  A             discretizing_filters/genericfilter.h   
> [License: GPL (v2+)]
>  D             discretizing_filters/kstfilter_generic.cpp  
>  D             discretizing_filters/kstfilter_generic.xml  
>  A             
> discretizing_filters/kstobject_discretizing_filters.desktop