patch 8.1.1076: file for Insert mode is much too big

Problem:    File for Insert mode is much too big.
Solution:   Split off the code for Insert completion. (Yegappan Lakshmanan,
            closes #4044)
diff --git a/src/Make_sas.mak b/src/Make_sas.mak
index 6ba00fb..09650c3 100644
--- a/src/Make_sas.mak
+++ b/src/Make_sas.mak
@@ -114,6 +114,7 @@
 	hardcopy.c \
 	hashtab.c \
 	indent.c \
+	insexpand.c \
 	json.c \
 	list.c \
 	main.c \
@@ -174,6 +175,7 @@
 	hardcopy.o \
 	hashtab.o \
 	indent.o \
+	insexpand.o \
 	json.o \
 	list.o \
 	main.o \
@@ -234,6 +236,7 @@
 	proto/hardcopy.pro \
 	proto/hashtab.pro \
 	proto/indent.pro \
+	proto/insexpand.pro \
 	proto/json.pro \
 	proto/list.pro \
 	proto/main.pro \
@@ -373,6 +376,8 @@
 proto/hashtab.pro:	hashtab.c
 indent.o:		indent.c
 proto/indent.pro:	indent.c
+insexpand.o:		insexpand.c
+proto/insexpand.pro:	insexpand.c
 json.o:			json.c
 proto/json.pro:		json.c
 list.o:			list.c