play button must be disabled until video is actually ready for playing

[jellegerbrandy]

Reproduce:

1. go here: https://staging.paratii.video/play/8?playlist=4
2. Click on "play"
3. See a black screen (until the vid s downloaded, which may take ages)

The paly button must be disabled until the vid is ready to play.

(Once we have implemented #154 , this behavior may cahnge)

[eliawk]

@ya7ya / @jellegerbrandy is there any "videoIsReady" method, or something to check if there is enough data to start the streaming?

[geckoslair]

think that #236 is rising in priority

[jellegerbrandy]

I think this is superseded by the plands to migrate to Clappr, plus the fact that we now have #154 . Closing