This function updates the netsim_dat object given a
network representing the current state of the simulation.
Details
If running tergmLite simulation, this function updates
x$el[[network]] and (if tergmLite.track.duration is TRUE
for the network index network) the network attributes "time"
and "lasttoggle" in x$net_attr[[network]]. If not running
tergmLite simulation, this function updates the networkDynamic
object stored in x$nw[[network]]. The input nw should be of
class networkLite when running tergmLite simulation, and of
class networkDynamic when not running tergmLite simulation.