Exit rather than return

src/freedombone-image-mesh

 	echo $'Compiling toxcore' >> $INSTALL_LOG
 	if [ ! -d $INSTALL_DIR/toxcore ]; then
 		echo $"$INSTALL_DIR/toxcore not found" >> $INSTALL_LOG
-		return
+		exit 63856
 	fi
 	cd $INSTALL_DIR/toxcore
 	SECONDS=0
 		echo $"Toxcore compile failed at $(($duration / 60)) minutes and $(($duration % 60)) seconds elapsed." >> $INSTALL_LOG
 		echo $'Unable to make toxcore' >> $INSTALL_LOG
 		echo $'See $INSTALL_DIR/make_toxcore.txt' >> $INSTALL_LOG
-		return
+		exit 73835
 	fi
 	rm $INSTALL_DIR/configure_toxcore.txt
 	rm $INSTALL_DIR/make_toxcore.txt
 
 	if [ ! -f /usr/local/bin/tox-bootstrapd ]; then
 		echo $"File not found /usr/local/bin/tox-bootstrapd" >> $INSTALL_LOG
-		return
+		exit 37825
 	fi
 
 	useradd --home-dir /var/lib/tox-bootstrapd --create-home --system --shell /sbin/nologin --comment $"Account to run Tox's DHT bootstrap daemon" --user-group tox-bootstrapd
 
 	if [ ! -d $INSTALL_DIR/toxic ]; then
 		echo $"$INSTALL_DIR/toxic not found" >> $INSTALL_LOG
-		return
+		exit 347835
 	fi
 
 	cd $INSTALL_DIR/toxic