added complete-scan feature

- Added the complete scan option (targeting: 192.168.1.2-255)
- Added radio button in the GUI to switch between scan options
- Already implemeted the GUI for (possible) future feature about
  band limits.
Couple of fixes

- Typo
- Added exception handler in case 'timer' wasn't already setted
enabled GTK UI up/download limit widget
added bandwidth limit functionality

- Updated README file.
- Bumped version.
Added whitelist and support for ranges
updated README to report new features
bumped version

- And commited new auto-updated egg-info