Scroll editor into browser view on cursor movement

[danyaPostfactum]

I use ACE as textarea replacement on some pages. When cursor is moved below bottom (or above top) window edge, ace should scroll cursor into browser view (default textarea behavior)

[nightwing]

https://github.com/ajaxorg/ace/tree/textarea fixes scrolling and adds basic support for this.
Since main usecase of ace is a full page editor, and scrolling into view can have side effects (e.g. firefox will scoll elements with overflow:hidden) it should be explicitly enabled with editor.setAutoScrollEditorIntoView();
Do you think editor.setAutoScrollEditorIntoView(false); for disabling it is needed?

[danyaPostfactum]

I have toggleable "fullscreen" mode for editing areas, so maybe I need the way to enable/disable this. But I'm not sure, that FireFox issue affects editor container with position:fixed..

[lennartcl]

Addressed with #1240.