Update runtime files.

runtime/syntax/bash.vim

@@ -0,0 +1,20 @@
+" Vim syntax file
+" Language:	bash
+" Maintainer:	Bram
+" Last Change:	2019 Sep 27
+
+" quit when a syntax file was already loaded
+if exists("b:current_syntax")
+  finish
+endif
+
+" The actual syntax is in sh.vim and controlled by buffer-local variables.
+unlet! b:is_sh
+unlet! b:is_kornshell
+let b:is_bash = 1
+
+runtime! syntax/sh.vim
+
+let b:current_syntax = 'bash'
+
+" vim: ts=8