Issue #2491155 by mikeburrelljr, Mac_Weber, opdavies: Update drupal.org and kernel.org URLs in core modules (Follow-up to 2489912)

Issue #2031641 by aburrows, lauriii, nlisgo, Pol, redsquid, tuutti, LewisNyman, akalata, agviu, kallehauge, _nolocation, rpayanm, saki007ster, mdrummond, RavindraSingh, brahmjeet789: Change active class to is-active

Issue #2349759 by davidhernandez, mortendk, rteijeiro, harish86, Sumit kumar, saki007ster, Mukeysh, brahmjeet789, nitishchopra, falkendk, Maninder, Vidushi Mehta, Ashish sandil, jitendra verma, crowdcg, sivaji@knackforge.com, dernetzjaeger: Copy system templates to Classy.

Issue #2329767 by lauriii, alexpott, Cottser, sqndr: Move table classes from preprocess to templates.

Issue #806982 by lokapujya, gnuget, miqmago, shashi1028, Floydm, bfroehle, kathyh, sreynen: Tables should take an optional footer variable and produce <tfoot>.

Revert "Issue #806982 by lokapujya, gnuget, miqmago, shashi1028, Floydm, bfroehle, kathyh, sreynen: Tables should take an optional footer variable and produce <tfoot>."

This reverts commit 580fd45d.

Issue #806982 by lokapujya, gnuget, miqmago, shashi1028, Floydm, bfroehle, kathyh, sreynen: Tables should take an optional footer variable and produce <tfoot>.

Issue #1939008 by sun, joelpittet, gnuget, Gokul N K, sphism, drupalninja99, c4rl, Cottser, mdrummond, long wave, steveoliver, andypost, Fabianx | jenlampton: Convert theme_table() to Twig.