Rename crypto package in setup.py

Renaming from "python-crypto" to "pycrypto", since the latter is the
package from pip. Otherwise, tox would fail when attempting to
download "python-crypto".

Change-Id: I8b8948469e26d92887d259303dcb79eef333395e
Signed-off-by: Igor D.C <igor.duarte.cardoso@intel.com>