Automatically scroll find selection into view

[lkcampbell]

This PR fixes issue #3063 by forcing the editor to always scroll a find selection into view.

[redmunds]

Yes, this always shows selection horizontally, but it cancels the "center vertically" functionality. I see the same results with:

            editor.setSelection(cursor.from(), cursor.to(), false);
            //cm.scrollIntoView({from: cursor.from(), to: cursor.to()});

I think the problem may be that the Editor.centerOnCursor() function passes null as x position to this.setScroll(). Maybe that used to work and there was a change in CodeMirror. Try looking into cm.scrollIntoView() to see what it's doing.

[redmunds]

Done with initial review.

[lkcampbell]

@redmunds, good catch, I didn't even notice that behavior.

Fix submitted.

[redmunds]

Looks good. Merging.