Polygon clipping requires mpl, but it is now a dependency.  Remove warning.
Polygon clipping requires mpl, but it is now a dependency.  Remove warning.

rjeli/scikit-image,ajaybhat/scikit-image,vighneshbirodkar/scikit-image,rjeli/scikit-image,ajaybhat/scikit-image,ofgulban/scikit-image,paalge/scikit-image,rjeli/scikit-image,ofgulban/scikit-image,Hiyorimi/scikit-image,vighneshbirodkar/scikit-image,pratapvardhan/scikit-image,vighneshbirodkar/scikit-image,Hiyorimi/scikit-image,paalge/scikit-image,pratapvardhan/scikit-image,ofgulban/scikit-image,paalge/scikit-image