Resolve namespace issues
Add workaround for compile error on bool template argument of ArgArray struct
Squelch bcc32 warning on accessing the digits array
Squelch bcc32 warning on unused values
Fix warnings about redefinig macros and conditions always true
Disable "LConv" block for bcc32 compiler
Remove macro test for deprecated macro
Fix appveyor-build for cmake v3.13+

Else on windows across DLLs the vtable is not visible which causes linking error

the transition from v3 to v4 introduced an API change that format.h does
not provide printf functionality. to easi the transition we introduce a
define `FMT_FORMAT_PROVIDE_PRINTF` that will pull in printf.h from format.h

Added support for pre-c++17 experimental string_view

CMake's GNUInstallDirs knows where particular Linux architectures and
distributions want to have their libraries installed. In particular,
Debian-derived "multi-arch" distributions keep their libraries in triplet
sudirectories under /lib. Other "bi-arch" distributions keep 64-bit
libraries in /lib64.

Including GNUInstallDirs and using CMAKE_INSTALL_LIBDIR and
CMAKE_INSTALL_INCLUDEDIR means that fmt's libraries and header files are
installed in the correct locations.

Tested with OpenEmbedded and on Debian GNU/Linux 9 (the special naming only
applies when installing in /usr.)

FMT_VARIADIC_CONST - Support for const variadic methods

This is to avoid using functionality deprecated in C++17.

./fmt/fmt/format.h(308,10): warning : unknown pragma ignored [-Wunknown-pragmas]
         ^
1 warning generated.
format.cc In file included from fmt\fmt\format.cc:28:
fmt\fmt/format.h(308,10): warning : unknown pragma ignored [-Wunknown-pragmas]
         ^
fmt\fmt\format.cc(165,17): warning : 'strerror' is deprecated: This
function or variable may be unsafe. Consider using strerror_s instead.
To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for
details. [-Wdeprecated-declarations]
      buffer_ = strerror(error_code_);
                ^
C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt\string.h(178,24) :  note: 'strerror' has been explicitly marked deprecated here
_ACRTIMP char* __cdecl strerror(
                       ^
fmt\fmt\format.cc(78,37): warning : unused function 'strerror_s' [-Wunused-function]
static inline fmt::internal::Null<> strerror_s(char *, std::size_t, ...) {
                                    ^
3 warnings generated.

refactor: use attribute to remove -Wunused-function warnings instead of dummy function call