add npm package
aikin: add test
pass test
aikin: add new test unit on 100-doors
aikin: pass test
aikin: change test to make doors count be input
aikin: make test pass
aikin: add test about utils countFactor method
aikin: pass utils test
aikin: change door.spec.js
aikin: refactor
aikin: add floorAfterSqrt function
refactor
aikin: refactor door