implement PREFFIX_INVALID_MEDIA_ID pluxin.xml preference to disable UUID preffix for bad media ids via config #647

[hthetiot]

Testing

To test bugs/PreffixInvalidMediaId branch

cordova plugin remove cordova-plugin-iosrtc --verbose
cordova plugin add https://github.com/cordova-rtc/cordova-plugin-iosrtc#bugs/PreffixInvalidMediaId --verbose
cordova platform remove ios --no-save
cordova platform add ios --no-save

Then to disable preffix on bad media id, update config.xml or package.json if using recent cordova

cordova": {
    "plugins": {
      "cordova-plugin-whitelist": {},
      "cordova.plugins.diagnostic": {},
      "cordova-plugin-statusbar": {},
      "cordova-plugin-background-mode": {},
      "cordova-plugin-ipad-multitasking": {},
      "cordova-custom-config": {},
      "cordova-plugin-iosrtc": {
        "PREFFIX_INVALID_MEDIA_ID": "FALSE",
        "MANUAL_INIT_AUDIO_DEVICE": "FALSE"
      }
    },

<plugin name="cordova-plugin-iosrtc">
        <variable name="MANUAL_INIT_AUDIO_DEVICE" value="FALSE" />
        <variable name="PREFFIX_INVALID_MEDIA_ID" default="FALSE"/>
</plugin>

[hthetiot]

#734 or unique track Id in relation to Janus issue.