Add file for ideal coverage of client-server applications

[thozza]

To be able to generate some statistics about the coverage of components, we need some source of information about the ideal test coverage. We discussed this and we will start with a simple JSON or plain text file containing list of components to cover. Based on this information, we should be able to generate some report about the current coverage.

The file will be present the in the test cases directory, so it can be different for different types of software.