nosleep.cc: more robust handling of cases when the system resumes from hibernation/suspend/power-off state via WOL signals. Also, a more frequent probing for the systems activity when there is a possibility that the system is idle (i.e. it may be suspended). The latter mechanism is due to the possibility of a given 10 sec. sampling period indicating a false lack of activity (e.g. due to processor.exe pausing itself temporarily because of 'should_i_sleep' evaluation). An alternative of measuring for a longer period of time (instead of sequential 10sec. loop iterations/measures) could actually end up being more complex to deal-with as the system may go into suspension/hibernation during such a sampling wait period... So keeping it rather simple(ish).