Util to load test vector

[diehuxx]

Closes #196

[KendallWeihe]

the typing of the generics is also possible like this:

Suggested change

	let vectors: TestVectorFile<VectorInput, VectorOutput> =
	TestVectorFile::load_from_path(path);
	let vectors = TestVectorFile::<VectorInput, VectorOutput>::load_from_path(path);

both are semantically equivalent, but the type definition for the generics live in different places syntactically

I tend to prefer the proposed way but it's potato, potahto

[diehuxx]

TIL -- I like the latter option too, thanks for showing me!

[KendallWeihe]

this is eggsellent, love how we are able to to standardize the TestVector and TestVectorFile type structs

I do wonder if it would be wise to disambiguate crates/ versus something like internal-crates/ but I don't have any great ideas right now