update watchdog lib
remove unused watchmedo.py
change indentation
change indentation
move some common functions to separate module
fix imports
move all addon settings to a separate module

in preparation for supporting reloading
dont try to import FSEvents/WinAsync

will always fail anyway (fsevent require c extension,
async not implemented yet)
upstream changes: importing unsupported observer wont force ImportError anymore
Merge branch 'history-fix'