JiraIssueComment improvements

[agowa]

Context

• Add Set-JiraIssueComment to update a comment or one of its attributes like visibility
• Add Remove-JiraIssueComment to delete a comment.
• Add JiraSD "internal"-Flag handling to JiraIssueComment commands https://community.atlassian.com/t5/Answers-Developer-Questions/Service-Desk-comment-visibility-according-to-REST-API/qaq-p/560152

Description

Please improve the JiraIssueCommant commands to covere the whole issue comment lifecycle.