Cache arrays that depend on node status.
Cache arrays that depend on node status.

Arrays that depend on the status_at_node array are cached and
reset (through the reset_status_at_node method) when the node
status array is changed.

Ensure that node and link status are uint8 everywhere.

cmshobe/landlab,landlab/landlab,landlab/landlab,amandersillinois/landlab,amandersillinois/landlab,cmshobe/landlab,cmshobe/landlab,landlab/landlab