Add Ethlabs team (and remove RIG)

[cheeky-gorilla]

This PR adds the Ethlabs team, with Ansgar, Caspar and Francesco (formerly of Architecture and RIG teams).

Although Ethlabs is a new team, the members within are not, and we expect them to continue working on eligible work within Ethlabs for the foreseeable future. Thus this PR does not expand eligibility in any way, other than adding a new team to house these existing members. The three members will keep their existing start dates, it wont be reset alongside the creation of this team.

@adietrichs @casparschwa or @fradamt please comment on this PR with a brief overview of Ethlabs and why it should be added as an eligible team within Protocol Guild.

Other changes within this PR:

• RIG group removed, as the team was disbanded within the EF
• QED from RIG has been moved to the "Independent" category

[casparschwa]

Hey cheeky, thanks for setting this up! Quick intro on Ethlabs:

Ethlabs is an independent nonprofit R&D lab for Ethereum, founded this summer by a group of us coming out of the EF (including Ansgar, Francesco and me). The work is a direct continuation of what we did there: core protocol research and prototyping, done in the open (ethresear.ch, EIPs, specs) and peer reviewed. Current workstreams include fast finality, shorter slots, ACD moderation, etc.

On eligibility: this is the same people doing much of the same work under a different banner. All three of us are existing members, and the constraints listed in the membership docs (core-protocol tethered research, open production of artifacts, peer review) apply to Ethlabs the same way they did to our EF teams.

Two small fixes for the PR:

• it's "Ethlabs", not "EthLabs" (also in the PR title)
• QED should be removed rather than moved to Independent: he left the EF and is currently not working on core Ethereum