Make it possible to convert map arguments to long and insert nsecs in maps.

Make it possible to convert map arguments to long and insert nsecs in maps.

Necessary to measure latency, example below to better understand the kqueue
select(2) regression:

syscall:select:entry { @start[pid] = nsecs; }
syscall:select:return { @usecs = hist((nsecs - @start[pid]) / 1000); }