Started implementing interface for scanning views
Merge branch 'master' of https://github.com/Redth/ZXing.Net.Mobile

# By Tomasz Cielecki
# Via Jon (1) and Tomasz Cielecki (1)
* 'master' of https://github.com/Redth/ZXing.Net.Mobile:
  Putting back log messages.
  Fixed issue with Activity restarts.
iOS now uses new IZXingScanner interface and can pause scanning...