docs: Add flank component diagram

[jan-goral]

Fixes #1510

The architecture model above is based on well-known PresentationDomainDataLayering proposed by Martin Fowler.

Basing on the model above will be easy to:

• scale the presentation layer by adding necessary implementations.
• replace external data providers.
• separate third-party library code from the domain, for keeping code clean.
• consider each layer as a separate module if needed.
• deliver output builds for different configurations.
• deliver domain layer even as a standalone library.

[github-actions]

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[mergify]

Title does not follow the guidelines of Conventional Commits.
Please adjust title before merge and use one of following prefix:

• build - Changes that affect the build system or external dependencies (dependencies update)
• ci - Changes to our CI configuration files and scripts (basically directory .github/workflows)
• docs - Documentation only changes
• feat - A new feature
• fix - A bug fix
• chore - Changes which does not touch the code (ex. manual update of release notes). It will not generate release notes changes
• refactor - A code change that contains refactor
• style - Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
• test - Adding missing tests or correcting existing tests and also changes for our test app
• perf - A code change that improves performance (I do not think we will use it)

[github-actions]

Timestamp: 2021-03-24 10:07:11
Buildscan url for ubuntu-workflow run 682633117
https://gradle.com/s/v5fmfhbjxzpuu

[mergify]

Title does not follow the guidelines of Conventional Commits.
Please adjust title before merge and use one of following prefix:

• build - Changes that affect the build system or external dependencies (dependencies update)
• ci - Changes to our CI configuration files and scripts (basically directory .github/workflows)
• docs - Documentation only changes
• feat - A new feature
• fix - A bug fix
• chore - Changes which does not touch the code (ex. manual update of release notes). It will not generate release notes changes
• refactor - A code change that contains refactor
• style - Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
• test - Adding missing tests or correcting existing tests and also changes for our test app
• perf - A code change that improves performance (I do not think we will use it)