User visible:
 * Introduced the "Tab", "Selection" and "Comments" views, as per #1091
 * Fixed the following problems:
   * Clicking on a tab does not update scope name
   * Clicking on a highlight does not update scope name
   * Clicking on heatmap does not update scope name

Internal:
 * Change function names:
   * applyview -> applyView
   * applysor -> applySort
 * Move the `view` field from viewer's scope to rootScope
 * The `updateViewer` and `showViewer` methods of the Hypothesis class
   no expect a `viewName` parameter (alongside the list of annotations),
   which they use to update the `view` field of the rootScope.
 * Added a `getComments` RPC call in guest, to collect comments for comments
   scope.

Search refactoring 1 - try 2

This does the following:

 * Introduces the `viewFilter` service, to filter annotations according to a given query.
 * Factor out the filtering code from the controller into this new service. (As described in #1092)
 * Enhances the tab searching: now we can search for multiple tags.

https://en.wikipedia.org/wiki/Don%27t_repeat_yourself

It was hiding in the manage_new_data(). It generated the standalone url for the annotations in the old hardcoded way. Fixed.

Closes #1086

Only replace extra slashes with a single slash.

In the previous implementation we did a really unnecessary string conversion.

This solution is shorter and cleaner.
It does fix #1065 however it does not solve the underlying discussion about the document plugins unencoding.

Introducing email notifications to page owners.

Add V1 viewsort feature

The viewsort feature allows users to better control the annotations that appear in the sidebar. The view control allows users to select either SCREEN (in which the sidebar only displays annotations that are currently visible on screen) or DOCUMENT (All annotation on the page are visible in the sidebar). The sort feature allows users to sort annotations by newest, oldest, or location (where they fall in the document). Both controls are implemented in simple tabs below the topbar.

The sort feature is implemented using Angular's very useful OrderBy attribute on ng-repeat.

The view control is implemented using updateviewer.

I had accidentally screwed this up when I combined some CSS in
the past few commits.

Unwrap the "magic controls". It's unnecessary structure that
doesn't save much and this way the style doesn't need to include
a display property. They can be inline or block.

This should have been qualified before, so that it only applied to
the main content header.

A step toward unification, remove the distinction between app and
site layouts.

This makes it clearer that this is a link and calls attention to
the number of replies.

Follow 8cc8dbb by making the toolbar icons less 3D, letting their
features come through without the distraction of exaggerated depth.

I like the harder edges -- less depth, following the trend toward
flatter designs. As a third-party on the page, I think we benefit
from being minimalist and understated, so that we don't look
gaudy in comparison to minimalist sites.

I decided I thought the additional collapsedreplies and collapsereply
classes were unnecessary. Turns out I was right. I also managed to
remove some duplication in the annotation template, the reply count
and timestamp are laid out such that they each appear only once and
neither is inside the "controls".

This frees us up to remove the other mouse events, which makes this
a bit cleaner to my eyes. It also avoids passing the selection
through the scope, storing no state between events.

The sliding panels are totally unused. They can be brought back but
right now it's unnecessary structure. The most reasonable place to
relocate the card-emphasis was in the stream-list. After all, cards
go in streams. But I found the stream-list class wasn't actually
placed on the list, it was placed on the list items. That seems
counterintuitive, so I raised it up in the structure.

Afterward, to keep the emphasis looking correct, I changed the paper
class to not have padding, and moved that padding to the thread
instead. Then I had to change some things about the thread, including
using it as a class in the editor (which is consistent, and makes
some sense). That meant that some viewer-only tag styles were bleeding
over, so I worked on those to make the tag styles a little nicer.

Finally, I had to fix the hover shadow on the threads now, and opted
to go for a background darkening instead of a shadow, since it works
across both replies and top level threads, and makes things less
bouncy, which I find to be a relief.

All in all, I'm happy. Probably will make someone unhappy.