handle exception
Merge branch 'develop' of https://github.com/FlightFinder/OAG_Schedule into develop
handles invalid input and return JSON message
Merge pull request #24 from snickers2029/develop

enable sorting
merge Controller.java
Merge branch 'develop' of https://github.com/FlightFinder/OAG_Schedule into develop
change HTTPResponse.java to match the new result format
Merge pull request #25 from samzhao88/develop

Handle exception more properly and change HTTPResponse to match the new result format from finder
the missing sorting line in former commit