Use zero redundancy when number of ES nodes is 1

[pavolloffay]

Signed-off-by: Pavol Loffay [email protected]

ES operator does not allow single redundancy with single ES node.

oc logs elasticsearch-operator-5c76fb5664-4wtch -n openshift-logging        10:55 
time="2019-07-18T08:51:44Z" level=info msg="Go Version: go1.10.8"
time="2019-07-18T08:51:44Z" level=info msg="Go OS/Arch: linux/amd64"
time="2019-07-18T08:51:44Z" level=info msg="operator-sdk Version: 0.0.7"
time="2019-07-18T08:51:44Z" level=info msg="Watching logging.openshift.io/v1, Elasticsearch, , 5000000000"
time="2019-07-18T08:52:07Z" level=error msg="error syncing key (myproject/elasticsearch): Failed to reconcile Elasticsearch deployment spec: Wrong RedundancyPolicy selected 'SingleRedundancy'. Choose different RedundancyPolicy or add more nodes with data roles

[codecov]

Codecov Report

Merging #539 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #539      +/-   ##
==========================================
+ Coverage   91.97%   91.98%   +<.01%     
==========================================
  Files          69       69              
  Lines        3501     3504       +3     
==========================================
+ Hits         3220     3223       +3     
  Misses        196      196              
  Partials       85       85

Impacted Files	Coverage Δ
pkg/strategy/controller.go	97.6% <100%> (+0.05%)	⬆️

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[codecov]

Codecov Report

Merging #539 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #539      +/-   ##
==========================================
+ Coverage   91.97%   91.98%   +<.01%     
==========================================
  Files          69       69              
  Lines        3501     3504       +3     
==========================================
+ Hits         3220     3223       +3     
  Misses        196      196              
  Partials       85       85

Impacted Files	Coverage Δ
pkg/strategy/controller.go	97.6% <100%> (+0.05%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 74f523c...fef9bd3. Read the comment docs.