Updated dependencies and version of library
More priority to contentType param
Fixes #368
Merge branch 'master' of https://github.com/loopj/android-async-http

# By mareksebera
# Via mareksebera
* 'master' of https://github.com/loopj/android-async-http:
  Fixes #368
  More priority to contentType param
  Updated dependencies and version of library