GCC 7 and later warn about overflow/truncation when using
sprintf and related functions with fixed-size buffers.

Suppress the warning in schematest.cpp.

GCC 8 (incorrectly) warns about sign conversions in (constant)
array size expressions:

error: conversion to 'long unsigned int' from 'int' may
change the sign of the result [-Werror=sign-conversion]
     char schemaBuffer_[128 * 1024];

Make these expressions unsigned by adding a 'u' suffix to
the first operands.

Recent GCC versions warn about using memcpy/memmove to
write to a class pointer (-Wclass-memaccess).

Avoid the warnings by casting to void* first.

Closes #1086.
Closes #1205.
Closes #1246.

Removing always true if condition

Detect C++11 features for Developer Studio

This patch enables various C++11 features if the code is compiled with
Developer Studio compiler version 5.14 or higher.

Rename a few internal preprocessor macros to avoid naming conflicts

Unit Test: Parsing "128.74836467836484838364836483643636483648e-336" causes a crash

Unit Test: Parsing "0e100" in full precision mode causes UB

Fix strtod

until I know what the normal-precision algorithm really does...

Some more need to be fixed.

=D

Do not use an approximation to do this. Instead check if the result is Inf.

If the buffer only contains zeros, return 0.

MSVC: Autodetect RAPIDJSON_HAS_CXX11_NOEXCEPT, RAPIDJSON_HAS_CXX11_TYPETRAITS

Avoid `MissingProperty` Error from `SchemaValidator` when a none-zero length value is given as `default` for the property