Add flags for tabsearch, QR generator, and grab handle

[Ahrotahn]

This PR contains two commits, the first adds a flag that removes the tabsearch button (and it's keyboard shortcut), the second adds a flag to disable the QR generator for sharing page links.

Fixes #1553 and #1574

[PF4Public]

Awesome!

Did you avoid removing this empty padding on purpose? Could it be also incorporated into the patch?

[Ahrotahn]

I have a separate patch for removing the drag handle space, but I needed to do some more testing before submitting it.
It turns out that the flex layout compresses the tip marquee's space regardless of it's preferred size and the added padding, so the only change needed is the resizing of the handle.

I'll add that patch to the PR soon once I get some time. @Eloston I hope you don't mind me grouping up these patches like this! Doing it this way makes it so that their merge order doesn't need to be considered since the flags need to be added sequentially.

[PF4Public]

With the last patch it looks like this:

[Eloston]

@Eloston I hope you don't mind me grouping up these patches like this! Doing it this way makes it so that their merge order doesn't need to be considered since the flags need to be added sequentially.

I don't mind, thanks for letting me know!

[Eloston]

LGTM 👍