Inotify: Reload keyboard shortcut definitions when configuration changes

Inotify: Reload keyboard shortcut definitions when configuration changes

Despite having the inotify mechanism compiled in my WM, everytime I
changed a keyboard shortcut definition in the WMRootMenu via WPrefs
I was required to open the WMRootMenu (eg with the F12 key) for the
change to take effect...annoying.

So explicitly reload the key bindings when a modification inside
~/GNUstep/Defaults/ is detected. As the inotify mechanism calls the
function wDefaultsCheckDomains() when that happens, let's add a call
to rebind_key_grabs() in there.

Now it works fine and changes are automatically in effect once WPrefs
writes the menu.

PS: rebindKeygrabs() renamed to rebind_key_grabs()...