Provide a more detailed issue comment history.

The history of issue comments as currently stored in the jiraactions table do not provide for a complete history of the comments made on a given case. That is, if editing is allowed then the method of storing the last edit date and the last editor is insufficient for tracking the precise chain of comment activities. I would propose that the comment history allow for a finer grain comment history and a method for navigating this new functionality from the issue browser.
-m