Suspends the execution of the calling task for the specified amount of time.
Note that other tasks of the same thread will continue to run during the
wait time, in contrast to
core.thread.Thread.sleep, which shouldn't be
used in vibe.d applications.
import vibe.core.core : sleep;
import vibe.core.log : logInfo;
import core.time : msecs;
logInfo("Sleeping for half a second...");