change meta to be a consistency module implemented by JRAFT

[DongyuanPan]

#121
The framework of consistency module is preliminarily realized.This PR implements multi-raft group management with different business processors and linearly consistent reads. But there's a lot of work to be done.

1. A snapshot management module is also required to achieve fast recovery of the state machine.
2. Data fragmentation module. Implement automatic routing of data to the corresponding raft group.
3. The ability for new nodes to automatically join the original raft group. It means that the original raft node does not need to be restarted.

[codecov-commenter]

Codecov Report

Merging #122 (75c043b) into develop (aba2165) will decrease coverage by 2.40%.
The diff coverage is 0.00%.

@@             Coverage Diff             @@
##           develop     #122      +/-   ##
===========================================
- Coverage    45.54%   43.13%   -2.41%     
===========================================
  Files          106      114       +8     
  Lines         4514     4766     +252     
  Branches       673      697      +24     
===========================================
  Hits          2056     2056              
- Misses        2104     2356     +252     
  Partials       354      354              

Impacted Files	Coverage Δ
...org/apache/rocketmq/mqtt/meta/config/MetaConf.java	0.00% <0.00%> (ø)
...rg/apache/rocketmq/mqtt/meta/raft/MqttClosure.java	0.00% <0.00%> (ø)
...apache/rocketmq/mqtt/meta/raft/MqttRaftServer.java	0.00% <0.00%> (ø)
...ache/rocketmq/mqtt/meta/raft/MqttStateMachine.java	0.00% <0.00%> (ø)
...pache/rocketmq/mqtt/meta/raft/RaftGroupHolder.java	0.00% <0.00%> (ø)
...mqtt/meta/raft/processor/AbstractRpcProcessor.java	0.00% <0.00%> (ø)
...e/rocketmq/mqtt/meta/raft/processor/Constants.java	0.00% <0.00%> (ø)
...qtt/meta/raft/processor/CounterStateProcessor.java	0.00% <0.00%> (ø)
...mqtt/meta/raft/processor/MqttReadRpcProcessor.java	0.00% <0.00%> (ø)
...qtt/meta/raft/processor/MqttWriteRpcProcessor.java	0.00% <0.00%> (ø)
... and 6 more