Solid and Open Manta Ray 888 shield for use in stacking

A fully filled front visor piece to allow stacking (courtesy of my daughter Amy age 11). Added 2 and 10 stack versions of the solid one (apologies messed up on the original stack files - these are updated) Added open skeleton and open stacks ( works with PLA but maybe too fragile and failed with PETG) Intermediate 'holed' front piece for more rigidity but still allow air flow. (base stl and two stack test - untested as of 8/4