Revisited vertical positioning of floatingspace, extended by comments. Re-position on editor's change event.
Ported t/9764 CKEDITOR.tools.eventsBuffer.
Use eventsBuffers for events to reduce CPU load when re-positioning the space.
Re-factorized floatingspace plugin code.
Improved eventsBuffer documentation.
Do not cache editable - always get fresh value.
Fixed: set mode from pin to bottom when the space below it less than the height of the floatingspace.
Fixed: pin the space when editable is out of sight.
Improved: set mode to bottom if possible, e.g. when there's enough space below editable and the space is floating.
Changelog entry.
Merge branch 't/9816'