#107 Add change comments automatically

[U. Windl]

In xca 2.3.0 I noticed that I can change a template and then press OK without being asked for any confirmation of the changes to be saved. Also the comments tab does not contain any notice.

In contrast the comments tab for CSRs contains a date-tagged line saying that the request had been signed.

So I wonder whether it's possible (maybe optionally) to add some "change comments" automatically if an element had been changed.

(Looking at KeePass 2 there's a history showing changes, and you can actually show or revert to a previous version. That might be nice for xca also, but that'll be a somewhat bigger change I guess)