Now checking first for Statistics Toolbox, and using poissrnd if it exists.
Now checking first for Statistics Toolbox, and using poissrnd if it exists.

Now checking first for Statistics Toolbox, and using poissrnd if it exists. If the toolbox does not exist, it uses the local equivalent, iePoissrnd. Note. The local function does not produce identical results in linux and in osx.

Signed-off-by: Nicolas Cottaris <1ecff0e9e041a2fad35c4476e9a18ef36d442282@sas.upenn.edu>

isetbio/isetbio,isetbio/isetbio