add a hint for first level
thanks @TimNN redo/undo button issue
level 4 is now in new UI
Level 5 new UI
added ray checking for level 4 and 5
Update README.md
Update README.md
Create License Geogebra
expanded footer
license geogebra
Revert "license geogebra"

This reverts commit 6af116dc5dcd578440f983052c3d41948e27c116.
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up to level 10 new UI
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fix deployggb.js