vim-patch:8.0.0420: text garbled when the system encoding differs from 'encoding'

Problem:    When running :make the output may be in the system encoding,
            different from 'encoding'.
Solution:   Add the 'makeencoding' option. (Ken Takata)

2c7292dc5b

src/nvim/options.lua

@@ -1456,6 +1456,13 @@ return {
       varname='p_mef',
       defaults={if_true={vi=""}}
     },
+    {
+      full_name='makeencoding', abbreviation='menc',
+      type='string', scope={'global', 'buffer'},
+      vi_def=true,
+      varname='p_menc',
+      defaults={if_true={vi=""}}
+    },
     {
       full_name='makeprg', abbreviation='mp',
       type='string', scope={'global', 'buffer'},