Update README.md

[alexkarezin]

Description of what I changed

Adding a link to the high-level diagrams including module, library dependency and others (https://sourcespy.com/github/googlefhirgateway/). Built directly from source and updated on schedule. Intended to simplify developer's introduction to the project.

In the spirit of transparency - I am the author of the diagrams. Hope contributors find it useful.

E2E test

TESTED: Documentation-only change

Checklist: I completed these to help reviewers :)

• I have read and will follow the review process.
• I am familiar with Google Style Guides for the language I have coded in.
• My IDE is configured to follow the Google code styles.
• I ran mvn clean package right before creating this pull request and added all formatting changes to my commit.
• All new and existing tests passed.
• My pull request is based on the latest changes of the master branch.

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[alexkarezin]

@bashir2 Bashir, do you by chance have time to take a quick look and approve? I would much appreciate it!

[bashir2]

@bashir2 Bashir, do you by chance have time to take a quick look and approve? I would much appreciate it!

Thanks for creating this nice tool and applying it to our project. I need to look into more details and also discuss it with other contributors. Some basic questions for now: Is the SourceSpy tool open source? Also what is the schedule on which these diagrams are being updated? Do we have any control on that?

[alexkarezin]

@bashir2 Bashir, thank you so much for taking a look!

The diagrams produced by the tool can be licensed under the same terms as the project (I assume Apache2). I can denote it on every page if you consider it a better practice. The code analysis engine itself is not open source (same way as many other popular systems on GH like CodeCov, TravisCI etc).

A complete diagram refresh is activated automatically on schedule (weekly), but it will soon be triggered directly by the repository commits and happen with 10 min after the changes are detected.

Let me know if you have any other questions. Thank you for taking into consideration!