Add package prometheus to the index

index/prometheus.mk

@@ -0,0 +1,7 @@
+PACKAGES += prometheus
+pkg_prometheus_name = prometheus
+pkg_prometheus_description = Prometheus.io client in Erlang
+pkg_prometheus_homepage = https://github.com/deadtrickster/prometheus.erl
+pkg_prometheus_fetch = git
+pkg_prometheus_repo = https://github.com/deadtrickster/prometheus.erl
+pkg_prometheus_commit = master