Add FAQ regarding the meta key and alternatives in README

[Abhirup-99]

There is no specific key called meta on the keyboard and it would be better if we add additional info about the meta and alt key relation in the README.
Relevant discussion:
https://chat.zulip.org/#narrow/stream/206-zulip-terminal/topic/Alt.20.2F.20Meta.20keys

[avats-dev]

This chat reference is giving 404. @Abhirup-99 can you guide me what needs to be done here? Thanks.

[Abhirup-99]

Hi @avats-dev, thank you for expressing interest in the issue.
There is no "meta" key on the keyboard, but alt serves as the meta key. We would like so documentation entry in the faqs section related to this. Research what's the meta key on mac/windows and make a small entry in the faqs section.

[zulipbot]

Hello @zulip/server-hotkeys members, this issue was labeled with the "area: hotkeys" label, so you may want to check it out!