oEmbed https issues

When using oEmbed on an https page, security conscious browsers such as Chrome won't load some of the http jsonp and swf content.

```
[blocked] The page at https://mydomain.org/mypage ran insecure content from http://flickr.com/services/oembed?format=json&url=http%3A//www.flickr.com/p…et-72157633424719011&jsoncallback=jQuery20006060085988137871_1372157077449.
```

In this PR, I've made the following providers protocol agnostic and tested this on both http and https:

- blip.tv
- dailymotion
- deviantart
- flickr
- ifixit.com
- img.ly
- instagram
- pastebin.com
- pinterest
- scribd
- slideshare
- soundcloud
- speakerdeck
- ted.com
- twitgoo
- twitpic
- vimeo
- youtube

The same approach would probably work for the other providers as well, but I haven't fixes and/or tested any of those yet.