Package rename: ome.scifio to io.scif

The ome.scifio package has been removed in favor of io.scif. This is the
first stage in separating the scifio-devel component to its own product.
It also avoids package clashing with, for example, Bio-Formats 4.4.5 and
later, which contain a scifio-devel component under the ome.scifio
namespace - but do not the SCIFIO API.
Updated the scifio-devel group and artifact id

These are now io.scif and scifio, respectively. This prevents clashing
in Maven between the SCIFIO API jar and the Bio-Formats scifio-devel
component.