Major refactoring of the Notebook, Kernel and CodeCell JavaScript. * Kernel doesn't depend on Notebook or CodeCell. * CodeCell doesn't depend on Notebook, only Kernel. * All of the kernel management logic has been moved out of the Notebook into the Kernel. * Public methods of the Kernel (execute, complete, etc) take a callbacks object that registers the callbacks for that msg. (rebased, cherrypicked, by Bussonnier Matthias <bussonniermatthias@gmail.com>) (and tabs removed) Conflicts: IPython/frontend/html/notebook/static/js/codecell.js IPython/frontend/html/notebook/static/js/completer.js IPython/frontend/html/notebook/static/js/tooltip.js