Less restrictive types for reconstruct

[Kolaru]

Currently reconstruct for PCA have the following signature:

reconstruct(M::PCA{T}, y::AbstractVecOrMat{T}) where {T<:Real}

This can be slightly annoying if the PCA was fitted with Float32 (e.g. data loaded from some file for which it is standard) and then the y is generated independantly thus being Float64 and leading to MethodError.

Could these kind of restrictions be lifted? If yes I'll look into a PR for it.

[wildart]

Sure, transform & reconstruct can be mended to accept different parameter types. If you up to, PR is always welcome.

[wildart]

Thanks for fix.