This change does the following:
- Show the header on Linux/Windows when fullscreened, but not in the
player. Users might fullscreen the app when they’re not playing a video.
- Always show the header on OS X (even when fullscreened) since that’s
how the user will exit the video. We can work on adding auto-hiding to
it later.
function references in hyperx need to look like:
```
onloadedmetadata=${onLoadedMetadata}
```
and not:
```
onloadedmetadata="${onLoadedMetadata}"
```
also removed some unnecessary `torrent.ready` checks in the player.
No header on Linux and OSX, just a back button on mouseover
ESC exits fullscreen, or if already not in fullscreen, goes back
More accurate scrub position
Removed the calc(100% -38x) hack, replaced with flexbox
As of this PR (https://github.com/substack/hyperx/pull/22) to hyperx,
attributes are automatically converted to properties for the few cases
where they’re different: class, for, and http-equiv.
