Include <cstdint> where needed.

On Linux, <cstdint> is indirectly included by other headers such as
<string>, so we don't notice that it's missing. But in theory it needs
to be included to get types like uint32_t, and in practice MSVC needs it.
Undefine 'min' and 'max' macros.

Apparently MSVC defines 'min' and 'max' as preprocessor macros,
which breaks the build when graph.h tries to use those identifiers
as method names, so we need to #undef them.
FindYamlCpp: use SelectLibraryConfigurations.

Use the standard select_library_configurations CMake macro
to fill in YAMLCPP_LIBRARIES, instead of custom code.
Define NOMINMAX to avoid min() and max() macros.

Evil windows headers define min() and max() as macros, causing problems
when trying to use those identifiers for unrelated functions, including
some in the standard C++ library. Previously I had added #undefs
in graph.h, which is the only place where it was causing trouble.
Now it's also failing in qdatetime.h and other places; I don't know why
it wasn't failing there before.

So I'll take a more global approach: define NOMINMAX via the build system.
That makes the Windows headers not define these evil macros to begin with.
Merge branch 'qtquick-attempt' into winbuild

* qtquick-attempt:
  Don't use include() on FindProtobuf.
  Don't search for pkg-config.
Fix build of glew in Windows.

GLEW_STATIC must be defined when building glew as a static library
or including it in the program's sources.
Fix build of PhysicsDebugRenderer::Color.

For some reason, MSVC2013 doesn't want to do brace initialization
on the trivial POD struct Color, so I had to add an actual constructor.
Add comment explaining the NOMINMAX definition.
Fix winsock header conflict.

From the comment I left in the CMakeLists:

Several Qt headers include windows.h, which includes winsock.h by
default. The enet headers include winsock2.h. winsock.h and winsock2.h
can't both be included, since they have conflicting declarations.
Thus, to be able to include Qt headers and enet headers in
the same compilation unit, we define WIN32_LEAN_AND_MEAN so that
windows.h doesn't include winsock.h.

This also disables other windows headers and features,
which should speed up compilation.
Merge branch 'qtquick-attempt' into winbuild

* qtquick-attempt:
  Change the way the OpenGL debug callback is registered.
  Use glm::distance for comparison only between float vecs.
  Beginnings of a chat dialog.
  Maybe a readonly textedit is best, as that gives us selections.
  Reserve the chatText qstring, to prevent costly reallocs.
  Maybe instead of a model we'll just use a Text/qstring.
Fix calling convention of GL debug callback on Windows.
Merge branch 'qtquick-attempt' into winbuild

* qtquick-attempt:
  CMakeLists: mark QtQuick as required.