Added Servers util class with shutdownGracefully method

[codecov[bot]]

Codecov Report

Merging #12 into master will decrease coverage by 1.21%. The diff coverage is 0%.

@@            Coverage Diff             @@
##           master      #12      +/-   ##
==========================================
- Coverage   47.08%   45.87%   -1.22%     
==========================================
  Files          16       17       +1     
  Lines         378      388      +10     
  Branches       32       33       +1     
==========================================
  Hits          178      178              
- Misses        195      205      +10     
  Partials        5        5

Impacted Files	Coverage Δ
...main/java/com/salesforce/grpc/contrib/Servers.java	0% <0%> (ø)

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[codecov[bot]]

Codecov Report

Merging #12 into master will increase coverage by 0.83%. The diff coverage is 87.5%.

@@            Coverage Diff             @@
##           master      #12      +/-   ##
==========================================
+ Coverage   47.08%   47.92%   +0.83%     
==========================================
  Files          16       17       +1     
  Lines         378      386       +8     
  Branches       32       33       +1     
==========================================
+ Hits          178      185       +7     
- Misses        195      196       +1     
  Partials        5        5

Impacted Files	Coverage Δ
...main/java/com/salesforce/grpc/contrib/Servers.java	87.5% <87.5%> (ø)

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Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 7ee10e3...c3afd04. Read the comment docs.

[rmichela]

Does this warrant a unit test?

[joeyb]

Yeah, forgot to copy the tests over. They should be added now.