PR addressing Issue #171

[Max-Bladen]

Despite cim() handling pca and spca object via the same code, their output components are different. This PR adds the $x and $rotation components to the pca object.

This isn't the cleanest fix as it means there is essentially double ups in the pca object. pca.object$x are the variates while pca.object$variates is the contains the same values but is structured a list of length 1. Downstream functions (such as network() and cim() access these components differently. Will clean this up in the future