Change RowCountProber metric name to allow better grouping

Gemfile.lock

 PATH
   remote: .
   specs:
-    gitlab-monitor (0.0.10)
+    gitlab-monitor (0.0.11)
       pg (~> 0.18.4)
       quantile (~> 0.2.0)
       redis-namespace (~> 1.5.2)

lib/gitlab_monitor/database/row_count.rb

@@ -61,7 +61,7 @@ module GitLab
 
           results = @collector.run
           results.each do |key, value|
-            @metrics.add("#{key}_count", value.to_i)
+            @metrics.add("db_rows_count", value.to_i, query_name: key.to_s)
           end
 
           self

lib/gitlab_monitor/version.rb

 module GitLab
   module Monitor
-    VERSION = "0.0.10".freeze
+    VERSION = "0.0.11".freeze
   end
 end