Add to README more info on pre-requisites

[ofreyssinet-ledger]

Modifications in the ## Pre-requisites section of the README:

• Adding link to official React Native environment setup instructions.
• ### Android section:
  • Adding JDK 11 requirement.
  • Adding NDK & CMake with exact versions and how to install them.

Type

Documentation

Context

I got a new M1 mac so I'm setting up the environment and some necessary information is missing from the README

[github-actions]

Thanks for your contribution.
To be able to merge in develop branch, you need to:

• pass the CI
• if needed, run /generate-screenshots
• have a dev review
• have a QA review
• if needed, /upgrade-llc

Why /generate-screenshots ?

If your PR contains UI related changes,
it might be necessary to regenerate screenshots.

Why /upgrade-llc ?

If your PR requires an update to the ledger-live-common library,
once the PR is merged on develop on ledger-live-common side,
you need to run /upgrade-llc to switch back to ledger-live-common@develop here before merging.

[elbywan]

📝 👍