add app logo
Merge branch 'master' of github.com:dst-hackathon/socialradar-android

# By opal charoensit (3) and sam35060 (2)
# Via sam35060 (3) and opal charoensit (2)
* 'master' of github.com:dst-hackathon/socialradar-android:
  update FriendAdapter.java
  update screen title
  add ImageDownloader class and update home page.
  comment the image absolute path for mac
  set signup url and rename parameter to match with api