Make README more up-to-date

[igor-hnizdo]

• update batches to GH actions
• remove pre-modules go stuff
• update makefile info
• add info about certificates

[tsusanka]

Merged via https://github.com/trezor/trezord-go/commit/39d21970aae9f130b42c496f12fe11a6dfe5b7ae, I have added few other smaller things. Thanks!

[tsusanka]

@igor-hnizdo one last thing, do you think you could update the Changelog real quick?

[tsusanka]

Done in https://github.com/trezor/trezord-go/commit/9aa6576af6fabd557bc298d1a12b73170f467a07 👍

[igor-hnizdo]

@tsusanka ha I just wanted to get around to it :) thx, sorry

[tsusanka]

No worries, it was a quick one.