Use CLOCK_MONOTONIC for conditions

Using default CLOCK_REALTIME clocks it could happen that if time change
for daylight saving times the clock drift and the timeout became infinite.
With CLOCK_MONOTONIC this issue is not present.
Systems have to support pthread_condattr_setclock in order to use
monolitic clock.
Added a test to use conditions and timed wait.
Move code from src/tds to src/replacements (coherent with Windows
implementation).

Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Add a test for getpassarg function

Signed-off-by: Frediano Ziglio <freddy77@gmail.com>