Stacks on all views

[jrasm91]

Right now stacks only show up on the main timeline view, but we would like to expand this functionality to additional pages, such as albums, favorites, trash, etc.

The idea for albums is to allow the user to choose which assets in the stack should be shared. For example, if a stack has 4 pictures and only two are shared in the album, the album should show a stack of 2. The same can apply to other views as well. Basically, show a stack if a subset of stacked assets are visible in that view. This is a bit tricky in that we need to pick a primary asset, and it may need to be the case that this functionality only applies when the primary asset of a stack is in the view.