Skip deleting 'Update.exe' during first folder removal of uninstall routine

[caesay]

RandomEngy/VidCoder#979

Just looking at the logs here I noticed the uninstall routine tries to delete Update.exe during the main folder deletion, which fails, obviously, because Update.exe is running. We should avoid attempting to deleting self until the uninstall is finished. At the end of the uninstall routine there is already code to clean up Update.exe after it exits.