Allow searches on Backbone collection

README.txt

Usage:

collection.searchBy({attribute: "searched value", attribute: "searched value", ...});
collection.search("query");

collection-extension.js

_.extend(Backbone.Collection.prototype, {
       searchBy: function(attrs){
        if(_.isEmpty(attrs)) return null;
        return this.filter(function(model){
            for(var key in attrs){
                if(~model.get(key).toLowerCase().indexOf(attrs[key].toLowerCase())) return true;
            }
            return false;
        });
    },
    search: function(obj){
        if(_.isEmpty(obj)) return null;
        return this.filter(function(model){
            for(var key in model.attributes){
                if(~model.get(key).toLowerCase().indexOf(obj.toLowerCase())) return true;
            }
            return false;
        });
    }
});