patch 8.1.1785: map functionality mixed with character input

Problem:    Map functionality mixed with character input.
Solution:   Move the map functionality to a separate file. (Yegappan
            Lakshmanan, closes #4740)  Graduate the +localmap feature.
diff --git a/src/feature.h b/src/feature.h
index e46947d..e2166a1 100644
--- a/src/feature.h
+++ b/src/feature.h
@@ -166,10 +166,8 @@
 
 /*
  * +localmap		Mappings and abbreviations local to a buffer.
+ *			Now always included.
  */
-#ifdef FEAT_NORMAL
-# define FEAT_LOCALMAP
-#endif
 
 /*
  * +insert_expand	CTRL-N/CTRL-P/CTRL-X in insert mode. Takes about