Merge pull request #57 from hydra200238/master

get share by latlng
get_share_preview_on_map
add get_share_by_share_id function
set notification of the same post read together
add location limit in get_share_stream
get_user_around_question_with_answer_rate
answer rate
update answer rate
add coins for ask
add functiom - user_bought_coins
send back updated coins amount
add get_question_preview_by_user in question controller