This means mutiple generic generators and some inference helper
* take(n, generator)
* filter(predicate, generator)
* map(func, generator)
* repeat(generator, repeats)

By using non-trivially copyable types, we force libstdc++-9's variant to
properly enter the valueless-by-exception state for our stringification
test.

Related to #1511

support for generating test cases based on multiple template template
types combined with template arguments for each of the template template
types specified

e.g.
```
TEMPLATE_PRODUCT_TEST_CASE("template product","[template]",
			   (std::tuple, std::pair, std::map),
			   ((int,float),(char,double),(int,char)))
```
will effectively create 9 test cases with types:
std::tuple<int,float>
std::tuple<char,double>
std::tuple<int,char>
std::pair<int,float>
std::pair<char, double>
std::pair<int,char>
std::map<int,float>
std::map<char,double>
std::map<int,char>

Tested type is accessible in test case body as TestType
Unique name is created by appending ` - <index>` to test name
since preprocessor has some limitations in recursions

Closes #1454

The previous implemetation was just plain broken for most of
possible uses, the new one should work (even though it is ugly
as all hell, and should be improved ASAP).

Fixes #1436

This adds support for templated tests and test methods via
`TEMPLATE_TEST_CASE` and `TEMPLATE_TEST_CASE_METHOD` macros. These
work mostly just like their regular counterparts*, but take an
unlimited** number of types as their last arguments.

* Unlike the plain `TEST_CASE*` macros, the `TEMPLATE*` variants
require a tag string.

** In practice there is limit of about 300 types.

No matcher actually uses it, and there is no good reason for it,
as the best it can do for user is removing a single indirection
when using the pointer inside the matcher. Given the overhead of
other code that will be running during such time, it is completely
meaningless.

This also fixes compilation for PredicateMatcher<const char*>.

By default, it expands into a `static_assert` + `SUCCEED` pair, but
it can also be deferred to runtime by defining
`CATCH_CONFIG_RUNTIME_STATIC_REQUIRE`, which causes it to expand
into plain old `REQUIRE`.

Closes #1362
Closes #1356