add a readme

Author: dmitmel

.gitignore

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+README.md.html

README.md

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+# input-api
+
+[![go to the releases page](https://raw.githubusercontent.com/CCDirectLink/organization/master/assets/badges/releases@2x.png)](https://github.com/CCDirectLink/input-api/releases)
+
+This mod allows other mods to add rebindable key bindings.
+
+## Guide for modders
+
+Adding your input actions is incredibly simple. Firstly, you have to define an option in `sc.OPTIONS_DEFINITION` (as you normally would) which will be written to the save file and show up in the "Controls" tab:
+
+```javascript
+// it is recommended to do this in either `postload` or `prestart`
+sc.OPTIONS_DEFINITION['keys-jump'] = {
+  type: 'CONTROLS',
+  init: { key1: ig.KEY.CTRL, key2: undefined },
+  cat: sc.OPTION_CATEGORY.CONTROLS,
+};
+```
+
+And after that you have to add a localized label for your key binding:
+
+```javascript
+// there are other ways to do this, but here is the simplest
+// you have to put this in `main`
+ig.lang.labels.sc.gui.options.controls.keys.jump = 'Jump';
+```
+
+A good example of using this mod can be seen in the [Jetpack](https://github.com/CCDirectLink/CCJetpack) mod.