Adjust timing of overlapping wakeups test case
Use system time for timing wakeups

Monotonic time might not advance in suspend.
System time could change during test.

Choose lesser of the two evils.

[tests] Use system time for timing wakeups
Merge pull request #5 from spiiroin/time_source

Use system time for timing wakeups
Bump libiphb version to 1.0.2