Feature/drm_support

[rogerkerse]

Thank you a lot for @danielmarino24i for DRM support pull request #1445

I just took it and update to latest master branch

These are the examples from previous pull request:

This PR adds support for DRM streams on iOS (Fairplay) and Android (Playready, Widevine, Clearkey)

Example how this is used. Seperate drm prop has been added.

source={{
    uri: 'https://media.axprod.net/TestVectors/v7-MultiDRM-SingleKey/Manifest_1080p.mpd',
}}
drm={{
      type: DRMType.WIDEVINE,
      licenseServer: 'https://drm-widevine-licensing.axtest.net/AcquireLicense',
      headers: {
          'X-AxDRM-Message': 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ2ZXJzaW9uIjoxLCJjb21fa2V5X2lkIjoiYjMzNjRlYjUtNTFmNi00YWUzLThjOTgtMzNjZWQ1ZTMxYzc4IiwibWVzc2FnZSI6eyJ0eXBlIjoiZW50aXRsZW1lbnRfbWVzc2FnZSIsImZpcnN0X3BsYXlfZXhwaXJhdGlvbiI6NjAsInBsYXlyZWFkeSI6eyJyZWFsX3RpbWVfZXhwaXJhdGlvbiI6dHJ1ZX0sImtleXMiOlt7ImlkIjoiOWViNDA1MGQtZTQ0Yi00ODAyLTkzMmUtMjdkNzUwODNlMjY2IiwiZW5jcnlwdGVkX2tleSI6ImxLM09qSExZVzI0Y3Iya3RSNzRmbnc9PSJ9XX19.FAbIiPxX8BHi9RwfzD7Yn-wugU19ghrkBFKsaCPrZmU'
      },
}}

We use it in production for over a year now and it works for us on Android and iOS.