Added State Layouts and a few niceties like examples, git hooks, etc

readme.md

@@ -15,7 +15,7 @@ The crate is still being built to a milestone plan:
   four measurement types, with a validation suite against Orekit reference
   trajectories.
 - **M2** — general-purpose completion: higher-degree gravity fields, more
-  density models, box-wing SRP and eclipses, manoeuvres, covariance propagation,
+  density models, box-wing SRP and eclipses, maneuvers, covariance propagation,
   relative motion, TLE and CCSDS I/O.
 
 The tables under [Validation](#validation) and [Performance](#performance) are
@@ -25,12 +25,13 @@ the acceptance criteria.
 
 - Everything is SI
 - Time is typed, using `hifitime`
+- US English spelling
 
 ## Foundations
 
 These are depended on, not reimplemented.
 
-| Crate | Licence | Provides |
+| Crate | License | Provides |
 |---|---|---|
 | [`hifitime`](https://crates.io/crates/hifitime) 4.3 | MPL-2.0 | TAI/TT/ET/TDB/UTC/GPS time scales, leap seconds |
 | [`anise`](https://crates.io/crates/anise) 0.10 | MPL-2.0 | Reference frames, planetary ephemerides, SPICE-format kernels |
@@ -75,6 +76,18 @@ figures, so the references are measured here rather than cited.
 | Full-force LEO, 1 day | not yet measured | — | — | — |
 | Ensemble of N states, scaling vs. cores | not yet measured | — | — | — |
 
-## Licence
+## Development
+
+Enable the pre-commit hook once per clone:
+
+```sh
+git config core.hooksPath .githooks
+```
+
+It runs `cargo fmt --check`, `cargo clippy --all-targets --all-features -- -D
+warnings`, `cargo test`, `cargo doc` with warnings denied, and a US English
+spelling check. `git commit --no-verify` skips it.
+
+## License
 
 MIT. See [LICENSE](./LICENSE).