patch 8.1.1927: code for dealing with script files is spread out

Problem:    Code for dealing with script files is spread out.
Solution:   Move the code to scriptfile.c. (Yegappan Lakshmanan, closes #4861)
diff --git a/Filelist b/Filelist
index af06f0c..3ab547a 100644
--- a/Filelist
+++ b/Filelist
@@ -90,6 +90,7 @@
 		src/regexp.c \
 		src/regexp_nfa.c \
 		src/regexp.h \
+		src/scriptfile.c \
 		src/screen.c \
 		src/search.c \
 		src/session.c \
@@ -225,6 +226,7 @@
 		src/proto/profiler.pro \
 		src/proto/quickfix.pro \
 		src/proto/regexp.pro \
+		src/proto/scriptfile.pro \
 		src/proto/screen.pro \
 		src/proto/search.pro \
 		src/proto/session.pro \