Swept:
`-Wpadded` in some places (where it caused extra size, instead of just
saying "hey, we padded struct at the end to align, just as standard says")
`-Wweak-vtables` everywhere (Clang)
`-Wexit-time-destructors` everywhere (Clang)
`-Wmissing-noreturn` everywhere (Clang)

The last three are enabled for Clang compilation going forward.

Also enabled `-Wunreachable-code` for Clang and GCC

All C++11 toggles are now removed. What is left is either platform
specific (POSIX_SIGNALS, WINDOWS_SEH), or possibly still needed
(USE_COUNTER).

If current CLion is compatible with `__COUNTER__`, then we should also
force `__COUNTER__` usage.

Changed
* CATCH_AUTO_PTR    -> std::unique_ptr
* CATCH_OVERRIDE    -> override
* CATCH_NULL        -> nullptr
* CATCH_NOEXCEPT    -> noexcept
* CATCH_NOEXCEPT_IS -> noexcept

Removed
* CATCH_CONFIG_CPP11_UNIQUE_PTR
* CATCH_CONFIG_CPP11_SHUFFLE
* CATCH_CONFIG_CPP11_TYPE_TRAITS
* CATCH_CONFIG_CPP11_OVERRIDE
* CATCH_CONFIG_CPP11_LONG_LONG
* CATCH_CONFIG_CPP11_TUPLE
* CATCH_CONFIG_CPP11_IS_ENUM
* CATCH_CONFIG_CPP11_GENERATED_METHODS
* CATCH_CONFIG_CPP11_NOEXCEPT
* CATCH_CONFIG_CPP11_NULLPTR
* CATCH_CONFIG_VARIADIC_MACROS

# By gnzlbg
# Via gnzlbg
* 'master' of https://github.com/gnzlbg/Catch:
  Conditionally removes usage of deprecated features

Conflicts (resolved):
	include/internal/catch_common.h
	include/internal/catch_section.hpp

-add macros to test for C++ version and features
to catch_compiler_capabilities.hpp
- replaces dynamic exception specifications (deprecated)
with noexcept in C++ Version >= 11
- defines defaulted copy constructor/move constructors/assignment
in C++ Version >= 11 since their implicit generation is deprecated
under some circumstances.
- fixes #259

- added throw() to streambuf destructor overrides (#182)

(and fixed up missing includes they uncovered)