Issue #1363112 by mparker17, mgifford, tlattimore, Jacine, dcmouyard, bowersox, ry5n, ahdiaz: Simplify names of 'element-x' helper classes.

Issue #1898428 by joelpittet, shanethehat, Floydm, gillbates, steinmb, artis, Cottser, gnuget: locale.module - Convert theme_ functions to Twig.