4th tab for object info

[andrewray]

When you look up object info with it goes through 4 stages.

1. Show types
2. Grow popup to show documentation
3. Hold the popup for 10 secs while typing
4. Send a code execution request with "identifier?".

The last one is a ipython thing. Its supposed to open the pager window with full documentation but in our case actually gets executed by ocaml which almost certainly leads to an error. This needs to be disabled in the javascript, if I can find it. Hopefully it can be done throught custom.js.