test-cli: add basic CLI invocation tests (16 tests)

[GreyCat]

This adds a way to test if our CLI invocation result in sensible and expected results or not.

What we want to test here covers:

• command line parsing library, its configuration, generation of --help and --version
• binding code which reads .ksy and writes target files
• higher level constructs which go above basic "compile 1 file" scenario — e.g. compilation of multiple inputs, handling custom output directory, handling more than 1 target and -t all.