Fix release metadata and repair the benchmarks

- repository pointed at the old host and the old repo name; this is the link
  crates.io and docs.rs display
- the readme example imported `differential_equations`, so it could not
  compile under the crate's published name
- `cargo bench` did not build: `Solution` borrows the ODE, so `.solve()`
  cannot be called on a temporary `Problem`. Bind it first.

Cargo.toml

@@ -1,11 +1,11 @@
 [package]
 name = "ordinary-diffeq"
-version = "0.3.0"
+version = "0.3.1"
 edition = "2021"
 authors = ["Connor Johnstone"]
 description = "A library for solving differential equations based on the DifferentialEquations.jl julia library."
 readme = "readme.md"
-repository = "https://gitlab.rcjohnstone.com/connor/differential-equations"
+repository = "https://git.rcjohnstone.com/connor/ordinary-diffeq"
 license = "MIT"
 exclude = ["roadmap/"]
 

benches/bs3_vs_dp5.rs

@@ -200,7 +200,8 @@ fn bench_interpolation(c: &mut Criterion) {
         let bs3 = BS3::new().a_tol(tol).r_tol(tol);
         b.iter(|| {
             black_box({
-                let solution = Problem::new(ode, bs3, controller).solve();
+                let mut problem = Problem::new(ode, bs3, controller);
+                let solution = problem.solve();
                 // Interpolate at 100 points
                 let _: Vec<_> = (0..100).map(|i| solution.interpolate(i as f64 * 0.05)).collect();
             });
@@ -213,7 +214,8 @@ fn bench_interpolation(c: &mut Criterion) {
         let dp45 = DormandPrince45::new().a_tol(tol).r_tol(tol);
         b.iter(|| {
             black_box({
-                let solution = Problem::new(ode, dp45, controller).solve();
+                let mut problem = Problem::new(ode, dp45, controller);
+                let solution = problem.solve();
                 // Interpolate at 100 points
                 let _: Vec<_> = (0..100).map(|i| solution.interpolate(i as f64 * 0.05)).collect();
             });

benches/simple_1d.rs

@@ -45,7 +45,8 @@ fn bench_interpolation_1d(c: &mut Criterion) {
     c.bench_function("bench_interpolation_1d", |b| {
         b.iter(|| {
             std::hint::black_box({
-                let solution = Problem::new(ode, dp45, controller).solve();
+                let mut problem = Problem::new(ode, dp45, controller);
+                let solution = problem.solve();
                 let _ = (0..100).map(|t| solution.interpolate(t as f64 * 0.1)[0]);
             });
         });

readme.md

@@ -1,4 +1,4 @@
-# DifferentialEquations
+# ordinary-diffeq
 
 A library, written in Rust, for integrating ordinary differential equations. For now, this is
 relatively simple, but it does have key features that are needed for orbit propagation, ray tracing,
@@ -47,7 +47,7 @@ pendulum problem):
 
 ```rust
 use nalgebra::Vector2;
-use differential_equations::prelude::*;
+use ordinary_diffeq::prelude::*;
 use std::f64::consts::PI;
 
 // Define the system (parameters, derivative, and initial state)