Add deactive namespace method

[kairbon]

this close #522

[codecov]

Codecov Report

Merging #521 into master will increase coverage by 0.09%.
The diff coverage is 66.66%.

@@             Coverage Diff              @@
##             master     #521      +/-   ##
============================================
+ Coverage     52.19%   52.29%   +0.09%     
- Complexity      177      182       +5     
============================================
  Files           103      103              
  Lines          3276     3291      +15     
  Branches        210      211       +1     
============================================
+ Hits           1710     1721      +11     
- Misses         1431     1432       +1     
- Partials        135      138       +3

Impacted Files	Coverage Δ	Complexity Δ
.../client/commandlinetool/DistkvCommandExecutor.java	0% <0%> (ø)	0 <0> (ø)	⬇️
...ava/com/distkv/asyncclient/DefaultAsyncClient.java	87.09% <100%> (+0.88%)	10 <1> (+1)	⬆️
...ava/com/distkv/namespace/NamespaceInterceptor.java	100% <100%> (ø)	4 <1> (+1)	⬆️
...in/java/com/distkv/client/DefaultDistkvClient.java	90.9% <100%> (+5.9%)	10 <1> (+2)	⬆️
...client/commandlinetool/CommandExecutorHandler.java	76.49% <50%> (-0.41%)	41 <1> (+1)
...n/java/com/distkv/parser/DistkvNewSqlListener.java	81.06% <50%> (-0.31%)	0 <0> (ø)

[ou-taku14]

Is there a problem with active Namespace operations multiple times?

[ou-taku14]

Thanks, LGTM~