Add action_url and notes_url links for hosts

This was added in NagMon 2.0.1. Host and service detail views now show a Links card with the action_url and notes_url defined for that object, and tapping one opens it in your browser.

A couple of notes on how it behaves: only http and https links are shown, and if a URL still contains unexpanded Nagios macros (like $HOSTNAME$) it's hidden rather than rendered as a broken link. So if you expect a link but don't see it, check how the URL comes through in your
server's statusjson.cgi output.