UI Improvements

[rhuss]

Epic for streamlining the UI experience, which includes wording of help message, output formats, consistent error and other messages ....

• Consistency in success and error messages #213
• Color Output #1589
• Improve traffic section in kn service describe #1590

[github-actions]

This issue is stale because it has been open for 90 days with no
activity. It will automatically close after 30 more days of
inactivity. Reopen the issue with /reopen. Mark the issue as
fresh by adding the comment /remove-lifecycle stale.