Disable CRT "secure" warnings

Suppresses 88 of the 213 warnings reported when compiling with
MSVC 2015 on AppVeyor.

src/CMakeLists.txt

@@ -44,6 +44,8 @@ if(${PLATFORM} MATCHES "Desktop")
     set(GRAPHICS "GRAPHICS_API_OPENGL_33")
     set_source_files_properties(rglfw.c PROPERTIES COMPILE_FLAGS "-x objective-c")
     link_libraries("-framework CoreFoundation -framework Cocoa -framework IOKit -framework CoreVideo")
+  elseif(WIN32)
+    add_definitions(-D_CRT_SECURE_NO_WARNINGS)
   endif()
 elseif(${PLATFORM} MATCHES "Web")
   set(PLATFORM "PLATFORM_WEB")