Alpha multi zero support

[darkn3rd]

Description

This adds the ability to create a comma separated list of multiple zeros for support dgraph versions for dgraph-io/dgraph#5116

This is forward and backwards compatible (thanks to Go template Sprig library)

• versions less than v1.2.3 will have single dgraph-zero.0 item for alpha --zero option
• versions equal or greater than v1.2.3 will have multiple zeros, e.g. dgraph-zero.0, dgraph-zero.1, dgraph-zero.2, up to number of zero.replicaCount specified by user

Types of tests:

• Test: helm install dgraph-test charts/charts/dgraph
  Result: dgraph alpha --zero will have 3 zeros
• Test helm install dgraph-test charts/charts/dgraph --set zero.replicaCount=5
  Result: dgraph alpha --zero will have 5 zeros
• Test helm install dgraph-test charts/charts/dgraph --set image.tag=v1.2.2
  Result: dgraph alpha --zero will have 1 zero

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This change is 

[danielmai]

Address comments and then it's good to merge.

Reviewed 2 of 2 files at r1.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @darkn3rd)

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charts/dgraph/templates/alpha-statefulset.yaml, line 21 at r1 (raw file):

Comma Seperated

Create a comma-separated list of Zeros

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charts/dgraph/templates/alpha-statefulset.yaml, line 25 at r1 (raw file):

supported dgraph version

supported by dgraph version

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charts/dgraph/templates/alpha-statefulset.yaml, line 26 at r1 (raw file):

"< 1.2.3" 

Check for < v20.03.1 too.

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charts/dgraph/templates/alpha-statefulset.yaml, line 29 at r1 (raw file):

Comman seperated List Zeros

Create a comma-separated list of Zeros

Also, remove trailing whitespace.

[darkn3rd]

Reviewable status: 1 of 2 files reviewed, 4 unresolved discussions (waiting on @danielmai)

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charts/dgraph/templates/alpha-statefulset.yaml, line 21 at r1 (raw file):

Previously, danielmai (Daniel Mai) wrote…

Comma Seperated

Create a comma-separated list of Zeros

Done.

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charts/dgraph/templates/alpha-statefulset.yaml, line 25 at r1 (raw file):

Previously, danielmai (Daniel Mai) wrote…

supported dgraph version

supported by dgraph version

Done.

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charts/dgraph/templates/alpha-statefulset.yaml, line 26 at r1 (raw file):

Previously, danielmai (Daniel Mai) wrote…

"< 1.2.3" 

Check for < v20.03.1 too.

Done.

---

charts/dgraph/templates/alpha-statefulset.yaml, line 29 at r1 (raw file):

Previously, danielmai (Daniel Mai) wrote…

Comman seperated List Zeros

Create a comma-separated list of Zeros

Also, remove trailing whitespace.

Done.