Add Replacejs through Bower

I'm about to make the accept/reject buttons post through AJAX instead of
doing a full page load. To make this easier I'm bringing in Replacejs
[1]. And to make JavaScript package management easier I also brought in
Bower [2].

JQuery is a dependency of Replacejs. We already had JQuery in our
application manifest, and I wasn't sure what version we're on. So I
didn't use the bower-imported JQuery version that came along with
Replacejs. @lencioni might have input on this.

[1] https://github.com/causes/replacejs
[2] http://bower.io/
Make Accept/Reject buttons AJAX:y

In order to make the review process smoother, I want accepting/rejecting
a snapshot less intrusive. If the accept/reject clicks are handled
asynchronously, no history entry will be added, therefor making it
easier to accept/reject a snapshot and then hit the back button to go
back to where you were. Before, you would go back to the same snapshot
again.

By using replacejs, I simply made the buttons re-render on XHR requests.
A following set of commits will

  A) Turn Accept/Reject into toggle(ish) buttons.
  B) Contextualize snapshot reviewing if you come from a sweep so that
  it is easy to move back and forth between snapshots under review.
Turn Accept/Reject into toggle buttons

This makes buttons stay in the place where they were clicked, which is a
win for usability.

I choose to bring the status-table into the replaced partial because of
the fact that the "Status" row changes depending on button clicks.
Improve styling of Accept/Reject buttons

By adding an icon and turning the buttons green/red depending on what
state they are in, we make it easier to quickly spot what state the
snapshot is in.
Iconize and move delete snapshot button next to header

The delete button took up way to much attention and space in its
previous location. Putting it next to the header makes it behave the
same way as for Urls in a Project, and makes accept/reject buttons stand
out more.
Give Accept/Reject buttons fixed width

By adding a min-width, the buttons don't "jump around" (that's a
technical term) as much.