Adding json_spec gem to test the API

Signed-off-by: Edmundo Perez <edmundo.perez@crowdint.com>
Including json_spec helper methods on RSpec

Signed-off-by: Edmundo Perez <edmundo.perez@crowdint.com>
Removing unnecessary unless, Adding API ApplicationController for returning json instead of redirecting

Signed-off-by: Edmundo Perez <edmundo.perez@crowdint.com>
Adding specs for Api::V1::PullsController and refactor

Signed-off-by: Edmundo Perez <edmundo.perez@crowdint.com>