Reworking new test summary CLI API to be more future proof.

Replacing --skip_summary argument with --summary argument that can be none but can also specify some other alternatives.

Right now it also allows 'minimal' (default) or 'compact' as well. There is no difference between these if targetting the current branch of galaxy-central on bitbucket - but compact will extend minimal with additional information about the command-line generated if targetting some work in progress I have available on github at (https://github.com/jmchilton/galaxy-central/compare/structured_tool_tests?expand=1) which add the option to generate a ton of structured data (including command-line) to tool tests.