4.7.1,2,3 Link Metric Collection

[arnout]

The prplMesh agent on Turris Omnia with OpenWrt needs to pass the certification test cases 4.7.1 through 4.7.3 as defined by the Wi-Fi CERTIFIED EasyMesh (tm) Test Plan.

Since all these tests are very similar, they are collected into a single milestone entry.

• [TASK] Link metric collection for Ethernet links #390 Link metric collection for Ethernet links
• [TASK] Link metric collection for WiFi links #792 Link metric collection for WiFi links
• [TASK] Pass flow 4.7.1 test in testbed #381 Pass flow 4.7.1 test in testbed
• [TASK] Pass flow 4.7.2 test in testbed #382 Pass flow 4.7.2 test in testbed
• [TASK] Pass flow 4.7.3 test in testbed #383 Pass flow 4.7.3 test in testbed

[arnout]

Moving to M2 since 4.7.1 and 4.7.2 are wireless backhaul.

This issue really should be split in two, but it's not worth the bother.