Sadd method does not work when adding a single member to a set

[EvanPlettGML]

This line:

redis-mock/lib/server/set.js

Line 11 in 84fed02

if (arguments.length <= 2) {

prevents sad from being called with a single member. Example code:

mockRedis = require("redis-mock").createClient();
mockRedis.sadd("setName", "member");

Since only two arguments are passed, the check on line 11 resolves to true, so the method immediately exits without adding the member to the set.

[EvanPlettGML]

Suggestion: change line 11 to
if (arguments.length < 2) {