Synopsis
		sfconvolve < _in.rsf > _out.rsf ker=_ker.rsf adj=n wrap=n

convolve input 2D image by kernel

Parameters
		bool adj=n [y/n] if y adjoint convolution, if n, convolution   string ker= convolution kernel file (auxiliary input file name)   bool wrap=n [y/n] if y, perform doughnut wrapping. if n, no wrapping