IPython 5.0.0b3 out

Nothing fancy again, getting closer to RC.

You know the dril:

TL:DR;

 $ pip install ipython --upgrade --pre

 - We broke 3 things in beta2. sorry about that:
    - Tooltip in Notebook that would always say [object, object], now fixed.
    - Completion would crash with Prompt_toolkit 1.0.0 (sorry we are
living on master)
    - Spyder.

This was due to an (unintentional) change of API, if you ever spot a
change of API which is not documented of don't have big deprecation
warning, don't blindly update your project(s), make sure we are aware
of the API change. Especially during beta/rc cycle.

 - Doc building fixed on windows, and missing labels.
 - many %%magics now have correct syntax highlighting in the terminal as well !
 - Completer can be dismissed with CtrlG/CtrlC, input buffer cleared
with CtrlC. (no, not with Esc for technical reason, more in changelog)
  - Fix some key bindings (mainly in Vi input mode) to better match readline.

There is a couple of issue we can't reproduce / figure-out:
  - can't type double quote : https://github.com/ipython/ipython/issues/9589
  - get stuck in completions (Aron Meurer on this list)

We'd appreciate feedback if you can/cannot reproduce, to narrow-down the reason.

A few requests have been marked as non-issues/ not feasible / later,
please have a look and make you voice heard if it really bother you as
well.

A couple of issues are marked as minor, and we will try to fix them soonish.
Pr welcome !

As usual thanks for all of those who pitched in !

-- 
M