Protect eps and epsParent against wrong indices

Summary:
Fixed loop over indices for vector states.

Added assert to check for right indices in polarisation vectors of vector and tensor particles.

Updated History.md.

Related with #12, !12 and T232.

Test Plan: Run all tests and check that output is the same.

Reviewers: tlatham, kreps, jback

Reviewed By: tlatham, jback

Tags: #evtgen

Differential Revision: https://phab.hepforge.org/D108