Add hollow feature to ellipse, cylinder, torus, cone, pyramid shapes.
Add "hollow" key to these shape syntax. Ex. /fill glass -s ellipse[hollow=true]

Add new shapes "hollow_*" instead of adding "hollow" key, because it needs extra key "thickness", which is unneed when hollow=false.
Syntax changed. -> Ex. /fill glass -s hollow_ellipse[thickness=2].

Improved hollow_cone and hollow_pyramid.

Plan to add "hollow_tetrahedron"

Opened a new issue for hollow_tetrahedron. Opening an issue for eash shape is better.