feat(package): Add main file to support import via browserify
feat(package): Add main file to support import via browserify

Jeremy017/angular-masonry,vrouet/angular-masonry,gillyb/angular-masonry,starkwang/angular-masonry,centogram/angular-masonry,evermax/angular-masonry,gillyb/angular-masonry,Yuyuu/angular-masonry,tomersimis/angular-masonry,passy/angular-masonry,evermax/angular-masonry,Delapouite/angular-masonry,tomersimis/angular-masonry,zorojean/angular-masonry,Jeremy017/angular-masonry,passy/angular-masonry,zorojean/angular-masonry,vrouet/angular-masonry,starkwang/angular-masonry,Yuyuu/angular-masonry,Delapouite/angular-masonry,centogram/angular-masonry