added browser test file
added browser test file

andykog/mobservable,andykog/mobservable,mobxjs/mobx,mobxjs/mobx,andykog/mobx,romseguy/mobservable,ryanbraganza/MOBservable,mweststrate/MOBservable,sandals/mobservable,mobxjs/mobx,dschalk/mobservable,sandals/mobservable,romseguy/mobservable,mobxjs/mobx,mweststrate/MOBservable,sandals/mobservable,dschalk/mobservable,ryanbraganza/MOBservable,andykog/mobx,romseguy/mobservable,ryanbraganza/MOBservable,dschalk/mobservable,mweststrate/MOBservable