mackerel-plugin-squid: add url link for mgr:info
mackerel-plugin-squid: add url link for mgr:info

mackerelio/mackerel-agent-plugins,hiroakis/mackerel-agent-plugins,hiroakis/mackerel-agent-plugins,mackerelio/mackerel-agent-plugins,hiroakis/mackerel-agent-plugins,xorphitus/mackerel-agent-plugins,xorphitus/mackerel-agent-plugins,xorphitus/mackerel-agent-plugins,hiroakis/mackerel-agent-plugins,mackerelio/mackerel-agent-plugins,mackerelio/mackerel-agent-plugins,xorphitus/mackerel-agent-plugins