Merge branch 'master' into core-updates
gnu: Add cssc. * gnu/packages/version-control.scm (cssc): New variable. * gnu/packages/patches/cssc-gets-undeclared.patch: New file * gnu/packages/patches/cssc-missing-include.patch: New file * gnu-system.am: Add gnu/packages/patches/cssc-gets-undeclared.patch and gnu/packages/patches/cssc-missing-include.patch