Added test for filewatcher.clear().
Added test for filewatcher.clear().

fotinakis/testem,testem/testem,johanneswuerbach/testem,johanneswuerbach/testem,paulot/testem,Addepar/testem,paulot/testem,fotinakis/testem,bradleylandis/testem,johanneswuerbach/testem,Addepar/testem,testem/testem,testem/testem,bradleylandis/testem,Addepar/testem,paulot/testem,Addepar/testem,bradleylandis/testem,fotinakis/testem