implement get_https_proxies in Country
add load,load_google_play,load_itunes_connect method in Ranking and remove review model and fix some model relation
implement function for create google play ranking model
fix accepts_nested_attributes_for
implement function for saving google play ranking and apps (without apps associations)
implement function for saving google play data (without publisher. ignore data duplication)
implement function for saving google play ranking without publisher
replace find to scope and resolve duplication of device
add MergeAttribute module
add exception in load method in AppItem
add created_at and updated_at to AppItem and fix updatable? method in AppItem
add ScreenShot model
replace accepts_nested_attributes_for to autosave
implement function for saving publisher
add proxy model
replace => to :
move function related to proxy to Proxy from Country
Merge pull request #4 from ryysd/save_gp_data

Save gp data