Fix for version 0.4.5

v0.4.6, 06/04/2014 -- minor fix
                    - corrected missing incomplete parameter on parse_fromfile
                      and parse_fromstring
                    - added support to run scan in background with sudo support
                      added NmapProcess.sudo_run_background()
                    - fixed issue with run() blocking when an error triggered
                      during the scan