fix issue#30

[hetenyi-domonkos]

currently running sudo make install fails with the following output, as reported by many users:

bash build.sh
=> Workon './src/oreo_black_cursors' ...
terminate called after throwing an instance of 'Gio::DBus::Error'
terminate called after throwing an instance of 'Gio::DBus::Error'
xargs: sh: terminated by signal 6
xargs: sh: terminated by signal 6
make: *** [Makefile:7: build] Error 125

This commit suggested by @JefteKeller here fixes the issue.