docs: improve <Audio> docs

Author: streamich

docs/Audio.md

@@ -5,19 +5,20 @@ FaCC that creates an `<audio>` element to play audio tracks, re-renders on audio
 ## Usage
 
 ```jsx
-import {Audio} from 'mol-fe-react/lib/Audio';
+import {Audio} from 'libreact/lib/Audio';
 
 <Audio autoPlay src='https://www.soundhelix.com/examples/mp3/SoundHelix-Song-2.mp3'>{(control, state) => {
   JSON.stringify(state, null, 4)
 }}</Audio>
 ```
 
+
 ## Props
 
 In addition to props below also accepts all [React's media events](https://reactjs.org/docs/events.html#media-events).
 
 ```tsx
-export interface IAudioProps {
+interface IAudioProps {
   src: string;
   autoPlay?: boolean;
   loop?: boolean;
@@ -36,6 +37,56 @@ export interface IAudioProps {
   - `volume` - optional, number, audio volume in `[0..1]` range, defaults to `1`.
   - `noJs` - optional, React element(s) to render insided the `<audio>` tag.
 
+
+## Arguments
+
+The `children` function receives two arguments, `audio` instance as *controller* and `state`.
+
+```jsx
+<Audio autoPlay src={src}>{(audio, state) =>
+
+}</Audio>
+```
+
+First argument is the `<Audio>` component instance with the following public signature.
+
+```ts
+interface IAudio {
+  el: HTMLAudioElement;
+  play();
+  pause();
+  seek(time: number);
+  volume(value: number);
+  mute();
+  unmute();
+}
+```
+
+, where
+
+  - `el` - `<audio>` element DOM node.
+
+The second argument is the state of the `<Audio>` component with the following signature.
+
+```ts
+interface IAudioState {
+  time?: number;
+  duration?: number;
+  isPlaying?: boolean;
+  muted?: boolean;
+  volume?: number;
+}
+```
+
+, where
+
+  - `time` - current time in seconds.
+  - `duration` - total audio track duration in seconds.
+  - `isPlaying` - whether the audio track is currently playing.
+  - `muted` - whether `muted` attribute is set on the audio element.
+  - `volume` - current volume in range `[0..1]`.
+
+
 ## Example
 
 Play a sample audio track with control buttons.

src/Audio/story.tsx

@@ -35,10 +35,13 @@ storiesOf('Generators/Audio', module)
         <button onClick={() => audio.volume(state.volume + 0.05)}>Volume +</button>
         <button onClick={audio.mute}>Mute</button>
         <button onClick={audio.unmute}>Unmute</button>
+
         <pre style={{fontFamily: 'monospace'}}>
           {JSON.stringify(state, null, 4)}
         </pre>
+
         <hr />
+
         <pre style={{fontFamily: 'monospace'}}>
           {`
 <Audio src={src}>{(audio, state) =>