…:types API docs

- Delete the PowerPoint-generated digram
- Refactor the module tree slightly, in order to wrap the module docs with `#[aquamarine]` attribute
- Flesh out the remaining blank spots in the typed array API docs
- Change the `Binary` trait to use an associated constant instead of a nullary method

- change from top-to-bottom to left-to-right
- make rectangles rounded

…opy around them

- Turn every node in the diagrams into a link to the relevant type's API docs

…t show up in docs.

… convenient `from_buffer()`

- Add `TypedArray::byte_length()`
- Add `JsTypedArray::{byte_offset, buffer}`
- Revert visibility of Binary back to public to enable typed array abstractions
- Add tests for buffer aliasing and argument validation
- Add tests for `byte_length`, `byte_offset`, and `buffer` methods

…l the metadata, avoiding extra FFI calls to

retrieve that data.

…ate modules

- Shorten `from_buffer_region` to `from_region`
- Add symmetric `to_region` method, which only requires a single `napi_get_typed_array_info` FFI call

- byte_offset -> offset
- byte_length -> size
- to_region -> region
- to_typed_array and region take &self
- JsArrayBuffer::region static method, for doc discoverability

- add tests about region validation

- make doc-related crates (doc-comment, aquamarine) optional
- `Binary` only requires `Clone`, not `Copy` or `Debug`
- `Region` API changes
  * still impls Copy but all its methods take a reference
  * range checks throw `RangeError` instead of panicking
- minor code improvements
  * copy-editing nit in doc comment
  * `buffer/types.rs` imports from `types_impl` not `types` so it's clear why it has private access
  * use `map_err` to clean up some code
  * simplify `detach` test helper function