Submission PRE

Submitted to PRE on 3/20/2019. Corresponds to v2 of the preprint https://arxiv.org/abs/1812.10722v2

First submission

Submitted to CPC on 12/31/2018. Corresponds to v1 of the pre-print https://arxiv.org/abs/1812.10722v1
Re-submitted to JCP on 01/20/2019.