vim-patch:8.0.1564: too many #ifdefs

Problem:    Too many #ifdefs.
Solution:   Graduate the +autocmd feature. Takes away 450 #ifdefs and
            increases code size of tiny Vim by only 40 Kbyte.
f2bd8ef2b4

src/nvim/globals.h

@@ -478,6 +478,8 @@ EXTERN int sc_col;              // column for shown command
 EXTERN int starting INIT(= NO_SCREEN);
 // true when planning to exit. Might keep running if there is a changed buffer.
 EXTERN bool exiting INIT(= false);
+// internal value of v:dying
+EXTERN int v_dying INIT(= 0);
 // is stdin a terminal?
 EXTERN int stdin_isatty INIT(= true);
 // is stdout a terminal?