implement blueprint creation, placement, saving and loading

README.md

@@ -6,11 +6,13 @@ logic mostly like https://git.crispypin.cc/CrispyPin/marble
 ## todo
 (more levels)
 story/lore
-blueprints
+timestamps in solutions and blueprints
+multiple input/output sets
 scroll level list
+scroll blueprint list
 make marble movement more consistent (`>o o<` depends on internal marble order)
 decide on marble data size (u32 or byte?)
-blueprint rotation
+blueprint rotation?
 
 ## file hierarchy
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