Finished dopri5, interpolation, and callbacks

Cargo.toml

@@ -9,6 +9,7 @@ edition = "2021"
 serde = { version = "1.0", features = ["derive"] }
 nalgebra = { version = "0.32", features = ["serde-serialize"] }
 num-traits = "0.2.15"
+roots = "0.0.8"
 
 [dev-dependencies]
 approx = "0.5"