[CSM] Add on_punchnode callback

doc/client_lua_api.txt

@@ -694,19 +694,23 @@ Call these functions only at load time!
 * `minetest.register_chatcommand(cmd, chatcommand definition)`
     * Adds definition to minetest.registered_chatcommands
 * `minetest.register_on_death(func())`
-    * Called when player die
+    * Called when the local player dies
 * `minetest.register_on_hp_modification(func(hp))`
     * Called when server modified player's HP
 * `minetest.register_on_damage_taken(func(hp))`
-    * Called when player take damages
+    * Called when the local player take damages
 * `minetest.register_on_formspec_input(func(formname, fields))`
-    * Called when a button is pressed in player's inventory form
+    * Called when a button is pressed in the local player's inventory form
     * Newest functions are called first
     * If function returns `true`, remaining functions are not called
 * `minetest.register_on_dignode(func(pos, node))`
-    * Called when a player digs a node
+    * Called when the local player digs a node
     * Newest functions are called first
     * If any function returns true, the node isn't dug
+* `minetest.register_on_punchnode(func(pos, node))`
+    * Called when the local player punches a node
+    * Newest functions are called first
+    * If any function returns true, the punch is ignored
 ### Sounds
 * `minetest.sound_play(spec, parameters)`: returns a handle
     * `spec` is a `SimpleSoundSpec`