update readme

readme.md

@@ -3,7 +3,54 @@ controls library for minetest
 
 ![](https://github.com/mt-mods/controls/workflows/luacheck/badge.svg)
 
+# Overview
+
+Utility library for control press/hold/release events
+
+# API
+
+## Supported controls
+
+* jump
+* right
+* left
+* LMB
+* RMB
+* sneak
+* aux1
+* down
+* up
+* zoom
+* dig
+* place
+
+## callbacks
+
+```lua
+controls.register_on_press(function(player, control_name)
+	-- called on initial key-press
+	-- control_name: see above
+end)
+
+controls.register_on_release(function(player, control_name, time)
+	-- called on key-release
+	-- control_name: see above
+	-- time: seconds the key was pressed
+end)
+
+controls.register_on_hold(function(player, control_name, time)
+	-- called every globalstep if the key is pressed
+	-- control_name: see above
+	-- time: seconds the key was pressed
+end)
+```
+
+
+# References
 
 used by https://github.com/Arcelmi/minetest-bows.git
-
 Original repo: https://github.com/Arcelmi/minetest-controls
+
+# License
+
+LGPL 2.1 (see `LICENSE` file)