table improve instr + small text in describing attributes

Makefile

@@ -7,7 +7,7 @@ DOCNAME = ObsCoreExtensionForRadioData
 DOCVERSION = 1.0
 
 # Publication date, ISO format; update manually for "releases"
-DOCDATE = 2024-04-08
+DOCDATE = 2024-06-11
 
 # What is it you're writing: NOTE, WD, PR, or REC
 DOCTYPE =  WD
@@ -20,13 +20,27 @@ IVOA_GROUP = Data Model
 # be called $(DOCNAME).tex
 SOURCES = $(DOCNAME).tex role_diagram.pdf Appendix.tex
 
-# List of pixel image files to be included in submitted package 
+# List of pixel image files to be included in submitted package
 FIGURES = role_diagram.svg
 
 # List of PDF figures (for vector graphics)
 VECTORFIGURES = role_diagram.pdf
 
 # Additional files to distribute (e.g., CSS, schema files, examples...)
-AUX_FILES = 
+AUX_FILES =
 
-include ivoatex/Makefile
+-include ivoatex/Makefile
+
+ivoatex/Makefile:
+	@echo "*** ivoatex submodule not found.  Initialising submodules."
+	@echo
+	git submodule update --init
+
+# update the registry record example from a locally running DaCHS
+sample-record.xml:
+	curl -s http://localhost:8080/getRR/__system__/obs-radio/obs_radio | xmlstarlet fo > $@
+
+STILTS ?= stilts
+
+test:
+	@$(STILTS) xsdvalidate sample-record.xml