Update to SDK 2.1.0

[igrr]

non-OS SDK 2.1.0 has been released, with support for 16 MB flash size, support for broadcast packets in ESP-NOW, fixes for ARP, UDP broadcast, and other issues.

[alex-yazdan]

Because of fixing ARP issue, It's important to upgrade to this SDK,
How long does it take to upgrade to this SDK ?

[igrr]

@alirezza updating libraries should probably take a couple of hours (there's usually some breakage, SDK archives repackaging, and LD script hacking involved). As for the other parts of the checklist, depends, I wouldn't venture a guess.

Also I must mention that the top priority now is to clear all the blocking issues and push a new stable release, even if it doesn't include an SDK update. Feel free however to contribute to this issue if you find it important.

[jonhp]

How about combining your top priority with the new SDK. Possibly one could help the other?

[capedra]

@igrr How's it going? Could you please implement this for the next version 2.4.0-RC2 ? Thanks!

[torntrousers]

+1 from me for getting the 2.1.0 SDK in the next release!

[hcs-svn]

+1 because of the fixed ARP bug (#2330). To get rid of this would be very important.