Organization

The VRS documentation has different parts:

This documentation, which describes the concepts, features, and principles of VRS.
The API Documentation, generated using Doxygen.
To generate the API documentation from the VRS code, run:
```
  cd <vrs_repo_top_level_folder>
  doxygen vrs/Doxyfile
```
You'll find the API documentation in html at website/static/doxygen/index.html.
Sample code, which is not functional, but demonstrates how to use the APIs.
- SampleRecordAndPlay.cpp demonstrates different ways to create a file, by dumping the whole content from memory to disk after creating all the records in memory, or by writing the record to disk while continuing to create records.
- SampleImageReader.cpp demonstrates how to read typical image records, that is, records containing metadata and an image.
- SampleRecordFormatDataLayout.cpp demonstrates how to read metadata blocks.
Sample apps, which are runnable apps (though not actually useful). The first app generates a VRS file with different record types containing made-up data. The second app reads that VRS file and verifies that the record content is as expected.