Adding a "Follow" checkbox on ExampleAppLog

[nicolasnoble]

The "Follow" checkbox will let users inspect the log buffer without getting dragged down to the end if the app's log is very active. Only ticking the box will make the scrolling move on its own.

[ifarbod]

This would be really useful for the console example as well, also I personally prefer naming it "Auto-scroll".

I tweaked this a little so it additionally does the same action as the "Scroll to bottom" button if you click the checkbox:

        if (ImGui::Checkbox("Auto-scroll", &AutoScroll))
        {
            if (AutoScroll)
            {
                ScrollToBottom = true;
            }
        }

[ocornut]

I have implemented a similar thing based on your suggestion @nicolasnoble, for both Log and Console examples.
The checkbox is inside an Options popup-menu which seems like a good idea to teach/promote a design that would scale to more options (but a little odd with a single option).

Both those Log/Example are not production quality code though..