Fix bug preventing installed workflow from being found

Thanks again for the update script, @Tyilo. The script updates the project workflow file perfectly. However, it could not update the installed workflow file for the following reasons (as I've found):

1. If `syncfolder` has a value set in the Alfred plist:
    1. A preceding `~` does not expand to the home folder path
    2. A trailing newline prevented the value from being interpreted as a valid path

This pull request fixes both of these issues, thus enabling the script to update the installed workflow when a custom `syncfolder` is set. :)