Issue #2402639 by Katiemouse, nitvirus, lakshminp, dernetzjaeger, emma.maria, gippy, kporras07, john guant, Prashant.c: Rename the footer regions in Bartik

Issue #2375673 by DickJohnson, LewisNyman, lauriii, emma.maria, sqndr, Wim Leers, stephr: Split Bartik's CSS into SMACSS style components