[GNU/Linux] Improve FS changes handling with the IN_CLOSE_WRITE event

I just merged a patch on watchdog that adds the IN_CLOSE_WRITE FS event to GNU/Linux (wil be part of watchdog 1.0.3). This may be a huge improvement to handle that event in Drive.

As seen in NXDRIVE-1800, copying a large file will result in millions of useless "file modified" FS events. In such scenario, and on GNU/Linux only, being able to only discern the "end of file write" FS event would save so much resources at every levels.