Improved Hide/Unhide Dataframe(s) dialog

[Vitalis95]

Fixes #7533
@rdstern @N-thony @lloyddewit , I have added 2 radio buttons(Hide &Unhide), this improvements simplify the dialog for the user

[rdstern]

@Vitalis95 I am not sure how this is supposed to work?

I had a number of data frames and hid some using the bottom right-click. (They just hid without showing the dialogue.) Then I pressed Unhide and it gave me your new dialogue. I then tried to unhide those that were hidden, though it listed all of them. And I couldn't use Add or double-click to put them into the receiver in unhide. They did go into the receiver with Hide. (But they were already hidden!

[Vitalis95]

@rdstern , have a look at it.

[N-thony]

@derekagorhom can you peer review this?

[lloyddewit]

looks good, just some small comments

[N-thony]

@Vitalis95 is this ready for re-review?

[Vitalis95]

@N-thony , yes. Could you test it?

[Vitalis95]

@N-thony , the reset issue is now ok.

[N-thony]

@lloyddewit over to you

[rdstern]

@Vitalis95 this is looking pretty good now.
So Hide, clicking at the bottom just hides the current data frame, and Unhide takes you to the dialogue.
a) I was initially thinking that we should disable unhide, at the bottom, when there is nothing to hide. But I now suggest we leave it as it is, as it is a neat way of getting to the Hide/Unhide dialogue!
b) But it is odd that when you click on Unhide you get to Hide in the dialogue. Could you either swap the top radio button s round or go to the unhide (second one) initially. I quite like Hide before Unhide in the dialogue. So I'd prefer to go to the second - Unhide - when you first click on Unhide at the bottom. (Ideally you then have hide as the default if you first go to the dialogue itself.) So keep it as it is now, if that's confusing!
c) But one change you need is that the dialogue remembers the old setting - and this time it shouldn't. Because it is now unhidden! So clear the Unhide receiver when you unhide. And I assume you want to clear the Hide receiver also when you hide through the dialogue!!!

[Vitalis95]

@rdstern , have a look at it for part c).

[rdstern]

@Vitalis95 looks fine now. Thanks.
Once @lloyddewit approves it will be good to merge.