Add usage include for the new builder

diff --git a/builder-support/usage.include.txt b/builder-support/usage.include.txt
new file mode 100644 (file)
index 0000000..3c9a2dc
--- /dev/null
+++ b/builder-support/usage.include.txt
@@ -0,0 +1,6 @@
+Supported MODULES values:
+  authoritative
+  recursor
+  dnsdist
+
+Not setting one of these will make the builder exit with an error, as building all programs in one go is not supported and usually not necessary.