Switch to a custom event system, where SDL pumps into

To do this we needed to take ThreadVariant out of love.thread, and move it to common.
This also changes event names, instead of 1/2-letter abbreviations, full names!

src/common/Variant.h

@@ -0,0 +1,73 @@
+/**
+* Copyright (c) 2006-2011 LOVE Development Team
+*
+* This software is provided 'as-is', without any express or implied
+* warranty.  In no event will the authors be held liable for any damages
+* arising from the use of this software.
+*
+* Permission is granted to anyone to use this software for any purpose,
+* including commercial applications, and to alter it and redistribute it
+* freely, subject to the following restrictions:
+*
+* 1. The origin of this software must not be misrepresented; you must not
+*    claim that you wrote the original software. If you use this software
+*    in a product, an acknowledgment in the product documentation would be
+*    appreciated but is not required.
+* 2. Altered source versions must be plainly marked as such, and must not be
+*    misrepresented as being the original software.
+* 3. This notice may not be removed or altered from any source distribution.
+**/
+
+#ifndef LOVE_VARIANT_H
+#define LOVE_VARIANT_H
+
+#include <common/runtime.h>
+#include <common/Object.h>
+
+#include <cstring>
+
+namespace love
+{
+	class Variant : public love::Object
+	{
+	private:
+		enum Type
+		{
+			UNKNOWN = 0,
+			BOOLEAN,
+			NUMBER,
+			CHARACTER,
+			STRING,
+			LUSERDATA,
+			FUSERDATA
+		} type;
+		union
+		{
+			bool boolean;
+			char character;
+			double number;
+			struct {
+				const char *str;
+				size_t len;
+			} string;
+			void *userdata;
+		} data;
+		love::Type udatatype;
+		bits flags;
+
+	public:
+		
+		Variant(bool boolean);
+		Variant(double number);
+		Variant(const char *string, size_t len);
+		Variant(char c);
+		Variant(void *userdata);
+		Variant(love::Type udatatype, void *userdata);
+		virtual ~Variant();
+
+		static Variant *fromLua(lua_State *L, int n);
+		void toLua(lua_State *L);
+	}; // Variant
+} // love
+
+#endif // LOVE_VARIANT_H