go-nsq: fix early termination blocked by lookupd sleep
Merge pull request #204 from mreiferson/early_termination_204

go-nsq: cannot stop reader within jitter period
examples: wait for clean exit
Merge pull request #205 from mreiferson/example_exits_205

examples: wait for clean exit
replace writer.Close() with write.close()

1. close(this.exitChan) in writer.close()
2. replace Mutex with transactionStat
Merge pull request #202 from datastream/master

go-nsq: fix bug in Writer
nsqd: cleanup some unnecessary exit code