bugfix in mcsolve with python callback function for the hamiltonian
ADDED: Collection of useful quantum info states
FIXED: Error for int check in basis function under py32
UPDATED: quantum_info module can now be loaded
updated development notebook for hamiltonians with mean-field tests with test for mesolve with list-function format, sesolve and experimental mcsolve
make python function callback hamiltonian behavior consistent between mesolve and mcsolve (that is, return matrix representation of Qobj instead of Qobj itself)
import and add alias names to cython based expectation value functions so tthat they can be accessed easily in user programs (todo: docstrings), for example in hamiltonian and collapse operator callback functions (which work with matrix/vector representations instead of Qobjs).
added notebook for testing and benchmarking different ways of calculating expectation values
use paul's new fast sparse reshape in operator_to_vector and vector_to_operator
updated notebook with state dependent hamiltonian callback functions: unified api between sesolve and mcsolve
minor cython performance tweaks
mesolve: minor performance tweaks and code cleanup (use cython expect function instead of python function)
Attempt to fix problem reported by Arne in issue #28
attempt to fix issue with empty dims entries. related to issue #28
Revert "attempt to fix issue with empty dims entries. related to issue #28"

This reverts commit ff83ccb281e5a15cd45437904f05a2eb3fbe32b8.
Revert "Attempt to fix problem reported by Arne in issue #28"

This reverts commit dba5f1e3a742cb7e6f0972d29e9e98ae9d9b8217.
New attempt to fix issue #28.
avoid problem dimension reduction for superoperators. better solution needed eventually.
clean up: remove unused imports
fixed some errors in superop_reps. made it python3 compatible. also fixed some problems with the corresponding unit tests