Synopsis
		sfcsmooth < in.rsf > out.rsf repeat=1 adj=n rect#=(1,1,...) diff#=(n,n,...)

January 2012 program of the month:
http://ahay.org/blog/2012/01/01/program-of-the-month-sfsmooth/

Parameters
		bool adj=n [y/n] run in the adjoint mode   bool diff#=(n,n,...) [y/n] differentiation on #-th axis   int rect#=(1,1,...) smoothing radius on #-th axis   int repeat=1 repeat filtering several times