Major refactoring of MWNT class.
Major refactoring of MWNT class.

Refactoring MWNT class with new call parameters.
Instead of using a single set of SWNT `n` and `m` chirality
parameters, the constructor now expects a list of `(n, m)`
tuples in order to build the MWNT in a manner consistent
with their definition in literature using
(n1,m1)@(n2,m2)@...@(nN,mM)-like notation.

androomerrill/scikit-nano,scikit-nano/scikit-nano,androomerrill/scikit-nano,scikit-nano/scikit-nano