Improved documentation

... and better logical testing of Rotate_Fn as used in dependency package VAST

Initial release of spatial dynamic factor analysis

This release is associated with revisions for:

Thorson, J.T., Fonner, R., Haltuch, M., Ono, K., and Winker, H. In review. Accounting for spatiotemporal variation and fisher targeting when estimating abundance from multispecies fishery data.

and

Thorson, J.T., Ianelli, J.N., Larsen, E., Scheuerell, M.D., Szuwalski, C., and Zipkin, E. In revision. Joint dynamic species distribution models: a tool for community ordination and spatiotemporal monitoring. Glob. Ecol. Biogeogr.