Does not build on VC++ 2013

[mfeemster]

I am running Visual Studio 2013 with update 4 installed. This code has multiple build issues.

1. In the pair and tuple specializations for print_container_helper::printer, it chokes on this line:

using ostream_type = print_container_helper<T, TChar, TCharTraits, TDelimiters>::ostream_type;

I've fixed it locally with this:

#ifdef _MSC_VER
    using ostream_type = std::basic_ostream<TChar, TCharTraits>;
#else
    using ostream_type = print_container_helper<T, TChar, TCharTraits, TDelimiters>::ostream_type;
#endif

This isn't the greatest fix because it hardcodes it to basic_ostream, rather than referencing print_container_helper::ostream_type, but at least it works.

2. Once that builds, the library is unusable since it now chokes on the main interface that a caller would use: the << operator.

template<typename T, typename TChar, typename TCharTraits>
inline typename enable_if<::pretty_print::is_container<T>::value,
       basic_ostream<TChar, TCharTraits> &>::type
       operator<<(basic_ostream<TChar, TCharTraits>& stream, const T& container)
{
    return stream << ::pretty_print::print_container_helper<T, TChar, TCharTraits>(container);
}

Cannot resolve to the proper type in your most basic example:

  std::vector<int> foo;
  foo.push_back(1);
  foo.push_back(2);
  foo.push_back(3);

  std::cout << "My vector: " << foo << std::endl;

VS says:

error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'std::vector<int,std::allocator<_Ty>>' (or there is no acceptable conversion)

The user must specifically add each type they want the overloaded << operator to work with, such as:

template <typename T>
struct is_container<std::vector<T>> : std::true_type { };

template <typename T1, typename T2>
struct is_container<std::unordered_map<T1, T2>> : std::true_type { };

IMHO, if the main example shows it working with a vector, then it should work like that out of the box without the user having to specifically enter each type they want to work with.

With those changes, I have it working locally. Thanks.