Fix issue #543
Fix issue #543

I added a match arm for the Escape key.

Ms2ger/glutin,ecoal95/glutin,bvssvni/glutin,notriddle/glutin,nc4rrillo/glutin,kornholi/glutin,tomaka/glutin,mmatyas/glutin,vberger/glutin,servo/glutin,mbrubeck/glutin,mbrubeck/glutin,ozkriff/glutin,adambadawy/glutin,mitchmindtree/glutin,tomaka/winit