[BZ#677360] Provide tooltip summarising file/folder metadata differences

Submitted by Kalin Agrawal

Description

Wishlist item: I am comparing two directories with sets of files that have identical contents. One side of Meld shows all the icons of folders and files with little stars on them. When I compare the files, they are identical. But I have no way of knowing what that star means.

I understand that across different platforms and color choices there might be different meanings for the different color-codings and icons. So, what if I hovered the mouse over the file or directory, or if I right-clicked it, and a quick summary of the reason for their differences (or similarities) was given. For example, if the files are the same contents but have different meta-data (like modification time or something), then it might say "This file has the same contents as its matched one. This file has been modified more recently than the other one."