new files added: test, pth support, user fs support
modified select, sleep tests to fit pth support,
time is still is deterministic, but it's hard to precalculate it and
timeout tests was simplified.
in mounts manager added checks and comments
'user space fs' type of mount is added
select zcall added and it's can handle only timeout but not selecting
fixed bugs in multithreading - sleep, nanosleep, select, poll are supported
new linkage params, new files installation, rest minor changes
readme updated
Merge pull request #150 from YaroslavLitvinov/dev

pth