Add red unmeasured icon to properties

in legacy/trac#16020 (moved) onionoo got support for the measured flag, we should display it on atlas to help relay operators like https://lists.torproject.org/pipermail/tor-relays/2017-May/012242.html with debugging.

The tooltip should include:

• unmeasured is expected for new relays
• not expected if your uptime is > x days (x=5?)