Track 2 - Service Bus - ATOM management API

[KieranBrantnerMagee]

We need to bring forward the ATOM management API.

There are two ways to approach this. Manually and mutate the existing, or attempt to create an autogen. More detail will be provided as we move further into this.

Would call out that however we approach this, sync with KieranBrantnerMagee about security issues that must be addressed in the VNext.

[KieranBrantnerMagee]

Moving Milestone to July, as this work has been split into parts, of which Queue management made its way out in June thanks to Yijun's good work.

[KieranBrantnerMagee]

Just a note from our triage discussion: we had been wondering if any of the routing stuff had to do with mgmt, I poked around a bit and didn't see anything obvious in the -mgmt package docs OR in the portal/CLI commands, but it did serve as a good opportunity to mention "migration" and "key regeneration/auth rules" as two things that we haven't touched on yet. This hasn't come up in the SB meetings so don't take this as pressure to include them, just mentioning here for posterity in case we (read: we == Kieran if my brain falls out) are wondering what surface area is still remaining.