Add similar sequences tab

[blakesweeney]

We can add a tab that shows all similar sequences for all pages. This is an improvment of our current similar sequence button which doesn't embedd the results within the page easily. The idea would be a tab, what when click on did a sequence search, or got the results of an existing sequence search and displayed the results on the same page as the sequence page. I think this can be done as an an embedding of the sequence search widget and clever use of the API.