update global progress from individual releases

We now have a graph with *five* different releases.

howto/upgrades/Makefile

@@ -3,3 +3,12 @@ PROG=predict-os
 
 data.png: data.csv
 	$(PROG) graph -o $@ --path $<
+
+# order of requisites matter here, the releases must be in
+# chronological order, otherwise the resulting data.csv file will be
+# out of order.
+#
+# (an out of order .csv file actually still works when doing the
+# graph, amazingly, but it just feels more tidy this way.)
+data.csv: buster/data.csv bullseye/data.csv bookworm/data.csv
+	(echo Date,release,count ; cat $+ | grep -v ^Date) > $@

howto/upgrades/data.csv

@@ -88,3 +88,29 @@ Date,release,count
 2023-05-08,bullseye,77
 2023-05-08,bookworm,1
 2023-05-08,buster,7
+2023-06-05,bullseye,78
+2023-06-05,buster,6
+2023-06-05,bookworm,2
+2022-10-03,bullseye,86
+2022-10-03,buster,12
+2022-11-08,bullseye,83
+2022-11-08,buster,12
+2022-12-05,bullseye,83
+2022-12-05,buster,11
+2023-02-06,bullseye,84
+2023-02-06,buster,11
+2023-04-08,bookworm,1
+2023-04-08,bullseye,75
+2023-04-08,buster,9
+2023-06-15,bullseye,76
+2023-06-15,buster,6
+2023-06-15,bookworm,4
+2023-08-29,bullseye,75
+2023-08-29,buster,6
+2023-08-29,bookworm,6
+2023-09-26,bookworm,41
+2023-09-26,bullseye,42
+2023-09-26,buster,5
+2023-10-02,buster,5
+2023-10-02,bookworm,42
+2023-10-02,bullseye,42