RFE: add capability to add tests to multiple suites

[jswaro]

Use case:

As a test writer, I would like to test my code against various permutations of setup and teardown functions without having to write a parameterized test harness for boiler plate code.

// instead of 

TestSuite(suite_variant_x, .setup = x_setup, .teardown = teardown_common);
TestSuite(suite_variant_y, .setup = y_setup, .teardown = teardown_common);

void __setup(int variable)
{
    api_setup(variable)
}

void setup_x(void)
{
   __setup(variant_x)
}

void setup_y(void)
{
  __setup(variant_y)
}

static inline void __api_test_function()
{
    int rc;
    rc = api_function(args...);
    cr_assert_eq(rc == SUCCESS);
}

Test(suite_variant_x, simple_api_call)
{
    __api_test_function();
}

Test(suite_variant_y, simple_api_call)
{
    __api_test_function();
}

I'd love the ability to one of the the following:

TestSuite(suite_variant_x, .setup = setup_x, ...)
TestSuite(suite_variant_y, .setup = setup_y, ...)

MultiTest(suite_variant_x, suite_variant_y, simple_api_call)
{

}

or

params = ({x}, {y}) // or for more complex statements, ({x, z}, {y, z}, {x, z'})
ParameterizedTestSuite(suite, .setup = parameterized_setup, .teardown = common_teardown, .params);

Test(suite, simple_api_call)
{
...
}

@Snaipe

[Snaipe]

This is something to consider for #204.

If we were to implement this, the simplest semantic way would be to simply provide a list of parents to the test.

I wonder though. If the contents are identical, maybe providing a way to create a test from an existing void (*)(void) function might be the easiest way to have something functional without breaking the test tree.