Both numpy and ipython are included in ERP5 SR which wendelin inherits
from, and are pinned there. Here are e.g. latest pin-ups for numpy and
ipython in erp5:

    e3144a8a    (version up eggs.)
    135570c9    (version up eggs.)

Furthermore: this is not only a cleanup. As e3144a8a shows current
version of numpy in erp5 is 1.10.4 and in wendelin we still have 1.9.2
which is unintentional downgrade compared to erp5.

Don't do that.

/cc @kazuhiko
/reviewed-by @Tyagov  (on nexedi/slapos!41)