Fix for version comparison from strings to semver (#4602)

* Fix for version comparison from strings to semver

See #3002 for more detail

* Adding minio version for validation

* Include pre-releases in the semver ranges

This is important when testing against alpha and beta builds of
Kubernetes along with environments that use pre-releases to denote
things other than pre-releases (e.g., gke denotes the environment
with a pre-releases)

stable/minio/Chart.yaml

@@ -1,7 +1,8 @@
 apiVersion: v1
 description: Distributed object storage server built for cloud applications and devops.
 name: minio
-version: 1.0.0
+version: 1.0.1
+appVersion: RELEASE.2018-03-16T22-52-12Z
 keywords:
 - storage
 - object-storage

stable/minio/templates/_helpers.tpl

@@ -35,9 +35,9 @@ Create chart name and version as used by the chart label.
 Return the appropriate apiVersion for networkpolicy.
 */}}
 {{- define "minio.networkPolicy.apiVersion" -}}
-{{- if and (ge .Capabilities.KubeVersion.Minor "4") (le .Capabilities.KubeVersion.Minor "6") -}}
+{{- if semverCompare ">=1.4-0, <1.7-0" .Capabilities.KubeVersion.GitVersion -}}
 {{- print "extensions/v1beta1" -}}
-{{- else if ge .Capabilities.KubeVersion.Minor "7" -}}
+{{- else if semverCompare "^1.7-0" .Capabilities.KubeVersion.GitVersion -}}
 {{- print "networking.k8s.io/v1" -}}
 {{- end -}}
 {{- end -}}