[atlas] New version of probe firmware released: 4500

Dear probe hosts and community,

few days ago we released the new version of RIPE Atlas probe firmware: 4500.

These are the technical details:

* RIPE Atlas probe software now supports two more architectures: TP-Link 
(for the next generation probes) and CentOS (for RIPE Atlas anchors).

* There is now support for one-off measurements for ping, traceroute, 
DNS, and HTTPget.

* We fixed a bug in DNS measurements in which, when querying local 
resolvers, more queries went to the last resolver.

* Fixed "error" : { "TUCONNECT" : "Success"}. Before this version DNS 
TCP and HTTPget reported an error message "Success".

When enough probes have been automatically upgaded to this new firmware, 
this will enable us to start testing the "one-off" or "near-real-time" 
measurements. We will enable this first for beta-testers, and after we 
fix the bugs reported by them, we will mae it available to all probe 
hosts, sponsors, and RIPE NCC members.

Regards,
Vesna