[GSoC] Comments in Sidebar Deck: Weekly Update

[Mohit Marathe]

Hello everyone,

In the last week, I worked on setting up a "broadcaster-listener"
relation between `CommentsPanel` and `SwPostItMgr`.
Since `SwPostItMgr` does all the processing of comments, the idea is
to make `CommentsPanel` listen to `SwPostItMgr` after the latter is
done with the processing of comments (like adding, deleting,
editing, etc.) and update the `CommentsPanel` in the sidebar
accordingly.

Also, I've implemented a way to update the `CommentsPanel` when a
new comment is added.

Thanks,
Mohit