IOCaml 0.4 server and kernels

This release adds a new server application (removing the requirement for
IPython to be installed at all) and 2 JavaScript kernels.

The packages have been logically reordered a bit;

* iocaml-kernel - equivalent to what was iocaml.0.3
* iocamljs-kernel - new; javascript kernels
* iocaml - new server application, replaces old iocaml.0.3

Installing iocaml should install all 3 packages.  The kernels can be individually installed if you want to still use IPython as the server.