Split "Extending & Embedding" into separate files, one per chapter.
diff --git a/Doc/Makefile.deps b/Doc/Makefile.deps
index d9738dc..ca658f7 100644
--- a/Doc/Makefile.deps
+++ b/Doc/Makefile.deps
@@ -26,6 +26,11 @@
 	doc/doc.tex
 
 EXTFILES= ext/ext.tex $(MANSTYLES) $(INDEXSTYLES) $(COMMONTEX) \
+	ext/extending.tex \
+	ext/newtypes.tex \
+	ext/unix.tex \
+	ext/windows.tex \
+	ext/embedding.tex \
 	texinputs/reportingbugs.tex
 
 TUTFILES= tut/tut.tex $(MANSTYLES) $(COMMONTEX)