Support CR profile

[tripu]

High-level meta-issue to keep track of tasks involved:

• Design checking of transition requests (specifically, CR) as GH issues #523 (automate approval of CR requests by the project manager):
  Echidna API / Echidna web UI / GH issues ⬅️ / some other approach.
• How to send the CfE:
  Do from new IPP Symfony code ⬅️ / do in script / do from Echidna / …
• Add parameter to API to indicate substantive or editorial change #524 Give submitters a mechanism to indicate whether changes are purely editorial, or substantive:
  There will be a new parameter for that.
• Improve detection of preliminary implementation/interoperability reports? specberus#39 (improve detection of preliminary implementation/interoperability reports).
• Detect if it's a CR coming from an edited REC (in such case the shortlink does not change; see diagram below).

[deniak]

Workflow agreed with Directors and Comm