Add OpenMetrics compatible endpoint

Signed-off-by: Pat Riehecky <riehecky@fnal.gov>

data/templates/Makefile.am

@@ -3,6 +3,7 @@ templatesdir = $(pkgdatadir)
 TEMPLATES = \
 	debug.html \
 	default.html \
+	metrics \
 	stats.html
 
 templates_DATA = \

data/templates/metrics

@@ -0,0 +1,19 @@
+# HELP opens Number of open connections.
+# TYPE opens Gauge
+opens {opens}
+# HELP reqs Number of requests.
+# TYPE reqs Counter
+reqs {reqs}
+# HELP badconns Number of bad connections.
+# TYPE badconns Counter
+badconns {badconns}
+# HELP deniedconns Number of denied connections.
+# TYPE deniedconns Counter
+deniedconns {deniedconns}
+# HELP refusedconns Number of refused connections due to high load.
+# TYPE refusedconns Counter
+refusedconns {refusedconns}
+# HELP binary_info Information about the binary
+# TYPE binary Info
+binary_info{name="{package}",version="{version}"} 1
+# EOF