Can't remove blockquote elements

[cillianderoiste]

Steps to reproduce:
https://www.raptor-editor.com/demo/enable-disable-ui
Select "[Your comment here]" and hit the blockquote button repeatedly.

Instead of toggling the blockquote element, every time the button is pressed, a new blockquote element is added around the selected element.

Tested in Firefox 41

[deeknow]

Thanks for reporting this issue @cillianderoiste - have tested this in Chrome (which seems fine, does not re-wrap the elements) and IE11 which is not adding the blockquote at all. Most likely related bugs. Will address them at the same time ASAP.

[deeknow]

see #170 for an earlier report on the IE11 issue