Twitter searching and embed

[philipjohn]

Adopted from #26

Provide a mechanism for livebloggers to search Twitter and choose tweets from those results to embed.

There should be two ways to do this;

1. An entire Liveblog entry can be a single tweet
2. A liveblog entry can have multiple tweets embedded within it

[maxhartshorn]

A little late here but this would be a very useful feature, It would make the liveblog competitive with other twitter curation services like ScribbleLive