sp_index_impl for u8 and i8?

[BentPen]

In lines 124-130 of src/indexing.rs:

sp_index_impl!(isize);
sp_index_impl!(i64);
sp_index_impl!(i32);
sp_index_impl!(i16);
sp_index_impl!(u64);
sp_index_impl!(u32);
sp_index_impl!(u16);

Is there a reason i8 and u8 are not included?

[mulimoen]

Not specifically, but those types won't allow very big matrices and dense matrices might be faster in those cases. Feel free to open a PR if you need them