cache config modifications during reload instead of declining (503)

[btrnka63]

Hello, referring to notes in the CHANGELOG for 2.14.0 and 2.14.1 and related GIT issues (see bellow), would it be possible to cache such config modification requests (like setting the downtime) instead of declining/denying (503 HTTP code)?

API: reject config modifications during reload with HTTP status 503. #9445
POST /v1/console/*: return HTTP 503 while Icinga is reloading. #9947

It causes troubles for users and automata to set mentioned downtime objects. In our case the reload takes 20mins.

[ar-nath]

ref/NC/#835503