Allow multiple version of singleton feature with featureUtility installFeature command

[jjiwooLim]

Fixes #17299

[bensonlatibm]

Looks good - only need to update all copyright headers to include 2021

[jjiwooLim]

#build

[LibbyBot]

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[LibbyBot]

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[LibbyBot]

The build jjiwooLim-17319-20210527-0823
https://wasrtc.hursley.ibm.com:9443/jazz/resource/itemOid/com.ibm.team.build.BuildResult/_Mu2AML72Eeu5V8GZL3dwAw
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[jjiwooLim]

The build failed with wlp.lib.extract_fat failures which are unlrelated to these changes

[jjiwooLim]

#libbybot

[LibbyBot]

Code analysis and actions

DO NOT DELETE THIS COMMENT.

WARNING: This pull request contains binary files, which should be managed in a Maven repository.

• 3 product code files were changed.

• Please describe in a separate comment how you tested your changes.

• 5 FAT files were changed, added, or removed.

• Check that the build did not break the affected FAT suite(s).

[bensonlatibm]

Looks good!

[bensonlatibm]

The wlp.lib.extract_fat failures are unlrelated to these changes. They will be fixed via
https://wasrtc.hursley.ibm.com:9443/jazz/web/projects/WS-CD#action=com.ibm.team.workitem.viewWorkItem&id=276597