Update makefile

restore backup also when compilation fails

Author: BeastyBlacksmith

makefile

@@ -11,11 +11,11 @@ ifdef CHAPTER
 	 -c :wq \
 	 book.tex
 endif
-	julia --color=yes pull_julia_code.jl
-	lualatex book
-	pythontex book
-	biber book
-	lualatex book
+	-julia --color=yes pull_julia_code.jl
+	-lualatex book
+	-pythontex book
+	-biber book
+	-lualatex book
 ifdef CHAPTER
 	mv book.tex.bak book.tex
 endif