Add progressFrequency prop

Resolves cookpete/react-player#50

README.md

@@ -80,6 +80,7 @@ Prop | Description
 `width` | Sets the width of the player
 `height` | Sets the height of the player
 `className` | Pass in a `className` to set on the top level element
+`progressFrequency` | The time between `onProgress` callbacks, in milliseconds
 
 #### Callback props
 

src/ReactPlayer.js

@@ -5,8 +5,6 @@ import React, { Component } from 'react'
 import { propTypes, defaultProps } from './props'
 import players from './players'
 
-const PROGRESS_FREQUENCY = 1000
-
 export default class ReactPlayer extends Component {
   static displayName = 'ReactPlayer';
   static propTypes = propTypes;
@@ -48,7 +46,7 @@ export default class ReactPlayer extends Component {
         this.props.onProgress(progress)
       }
     }
-    this.progressTimeout = setTimeout(this.progress, PROGRESS_FREQUENCY)
+    this.progressTimeout = setTimeout(this.progress, this.props.progressFrequency)
   };
   renderPlayer = (Player) => {
     const active = Player.canPlay(this.props.url)

src/props.js

@@ -7,6 +7,7 @@ export const propTypes = {
   width: PropTypes.oneOfType([ PropTypes.string, PropTypes.number ]),
   height: PropTypes.oneOfType([ PropTypes.string, PropTypes.number ]),
   className: PropTypes.string,
+  progressFrequency: PropTypes.number,
   soundcloudConfig: PropTypes.shape({
     clientId: PropTypes.string
   }),
@@ -32,6 +33,7 @@ export const defaultProps = {
   width: 640,
   height: 360,
   volume: 0.8,
+  progressFrequency: 1000,
   soundcloudConfig: {
     clientId: 'e8b6f84fbcad14c301ca1355cae1dea2'
   },