Move scriptapi to separate folder (by sapier)

On the lua side, notably minetest.env:<function>(<args>) should now
be replaced by minetest.<function>(<args>).
The old way is and will stay supported for a long time.

Also:
Update and clean up lua_api.txt (by celeron55)
Move EnvRef to lua and remove add_rat and add_firefly (by kahrl)
Add separate src/util/CMakeLists.txt, other minor fixes (by kahrl)

src/script/lua_api/l_noise.h

@@ -0,0 +1,134 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef L_NOISE_H_
+#define L_NOISE_H_
+
+extern "C" {
+#include <lua.h>
+#include <lauxlib.h>
+}
+
+#include "irr_v3d.h"
+#include "noise.h"
+
+class LuaPerlinNoise
+{
+private:
+	int seed;
+	int octaves;
+	float persistence;
+	float scale;
+	static const char className[];
+	static const luaL_reg methods[];
+
+	// Exported functions
+
+	// garbage collector
+	static int gc_object(lua_State *L);
+
+	static int l_get2d(lua_State *L);
+	static int l_get3d(lua_State *L);
+
+public:
+	LuaPerlinNoise(int a_seed, int a_octaves, float a_persistence,
+			float a_scale);
+
+	~LuaPerlinNoise();
+
+	// LuaPerlinNoise(seed, octaves, persistence, scale)
+	// Creates an LuaPerlinNoise and leaves it on top of stack
+	static int create_object(lua_State *L);
+
+	static LuaPerlinNoise* checkobject(lua_State *L, int narg);
+
+	static void Register(lua_State *L);
+};
+
+/*
+  PerlinNoiseMap
+ */
+class LuaPerlinNoiseMap
+{
+private:
+	Noise *noise;
+	static const char className[];
+	static const luaL_reg methods[];
+
+	static int gc_object(lua_State *L);
+
+	static int l_get2dMap(lua_State *L);
+
+	static int l_get3dMap(lua_State *L);
+
+public:
+	LuaPerlinNoiseMap(NoiseParams *np, int seed, v3s16 size);
+
+	~LuaPerlinNoiseMap();
+
+	// LuaPerlinNoiseMap(np, size)
+	// Creates an LuaPerlinNoiseMap and leaves it on top of stack
+	static int create_object(lua_State *L);
+
+	static LuaPerlinNoiseMap *checkobject(lua_State *L, int narg);
+
+	static void Register(lua_State *L);
+};
+
+/*
+	LuaPseudoRandom
+*/
+
+
+class LuaPseudoRandom
+{
+private:
+	PseudoRandom m_pseudo;
+
+	static const char className[];
+	static const luaL_reg methods[];
+
+	// Exported functions
+
+	// garbage collector
+	static int gc_object(lua_State *L);
+
+	// next(self, min=0, max=32767) -> get next value
+	static int l_next(lua_State *L);
+
+public:
+	LuaPseudoRandom(int seed);
+
+	~LuaPseudoRandom();
+
+	const PseudoRandom& getItem() const;
+	PseudoRandom& getItem();
+
+	// LuaPseudoRandom(seed)
+	// Creates an LuaPseudoRandom and leaves it on top of stack
+	static int create_object(lua_State *L);
+
+	static LuaPseudoRandom* checkobject(lua_State *L, int narg);
+
+	static void Register(lua_State *L);
+};
+
+NoiseParams *read_noiseparams(lua_State *L, int index);
+
+#endif /* L_NOISE_H_ */