[GSoC] Comments in Sidebar Deck: Weekly Update

[Mohit Marathe]

Hello everyone,

In the last week, I implemented sorting functionality. There are two 
options to sort: by position (default) and by time. For this, I modified
`populateComment()` to sort the vector of `SwFormatField*`, which I 
get from `SwPostItMgr::UpatePostItsParentInfo()` (which was 
initially part of `SwPostItMgr::AddPostIts`), according to time or 
position based on the option selected and repopulate the comments 
panel.
Apart from this I refactored some code that I wanted to re-use to 
avoid code duplication.

You can find the commit here: https://gerrit.libreoffice.org/c/core/+/170492/2

Thanks,
Mohit