[ISSUE #58] enable the service to support multiple namesrvs

[cserwen]

What is the purpose of the change

#58

Brief changelog

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Verifying this change

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[vongosling]

1 failing check, pls check it.

Failed tests:
OpsControllerTest.testHomePage:64 No value at JSON path "$.data"

[cserwen]

1 failing check, pls check it.

Failed tests: OpsControllerTest.testHomePage:64 No value at JSON path "$.data"

OK. I will fix it.

[zhangjidi2016]

If multiple namesrv services are deployed in a rocketmq cluster, namesrv addresses are connected using ';' by default. So there is a problem If ';' are used to divide multiple rocketmq clusters in here, it cannot distinguish between two namesrv addresses belonging to the same rocketmq cluster or to different rocketmq clusters.

[cserwen]

IMO, we don't need to distinguish whether namesrvs belong to the same cluster. Because if two namesrv points to the same cluster, we only need to choose one of them to work, right?

[cserwen]

@zhangjidi2016 However, we can also use @ to distinguish the namesrv of different clusters, just like this:

rocketmq.config.namesrvAddrs=localhost1:9876;localhost2:9876@localhost3:9876;localhost4:9876

I will fix it. :-D