@tsusanka: original issue trezor/trezor-firmware#685
Let's improve our documentation.

Firstly, we should extend mdBook on the whole monorepo not just the core/ section. trezor/trezor-firmware#686

We have agreed we are writing documentation for five roles:

1. Someone integrating Trezor who wants more info about connect or trezorlib.

• trezor/trezor-firmware#229 Document trezorlib API

2. Someone who wishes to contribute to trezor-firmware.

• #687 Check and document how to build
• #688 Check and document how to run emulators
• #689 Check and document how to run tests
• #690 Document protobuf communication
• #691 Document how to contribute to core using an example feature

3. Someone who builds Trezor's software themselves (reproducible build).

• #692 Check and document reproducible builds

4. Someone who builds Trezor including hardware (aka DYI).

• #693 Check and document hardware

5. Hard core "nerds" - detailed information about storage, used cryptography etc.

• #693 Check and document storage and trezor-crypto