First shot at merging the wiki documentation into the headers.

include/SDL_platform.h

@@ -186,7 +186,22 @@ extern "C" {
 #endif
 
 /**
- *  \brief Gets the name of the platform.
+ * Get the name of the platform.
+ *
+ * Here are the names returned for some (but not all) supported platforms:
+ *
+ * - "Windows"
+ *
+ * - "Mac OS X"
+ *
+ * - "Linux"
+ *
+ * - "iOS"
+ *
+ * - "Android"
+ *
+ * \returns the name of the platform. If the correct platform name is not
+ *          available, returns a string beginning with the text "Unknown".
  */
 extern DECLSPEC const char * SDLCALL SDL_GetPlatform (void);