Reduced space between annotation cards by 1/2. This is solves [issue 493](https://github.com/hypothesis/h/issues/493) and looks much nicer.

Dan wants us to use sans-serif fonts. I added a $sansFontFamily to the body element under //ELEMENT STYLES. It achieves the desired affect without screwing up anything as far as I noticed. Tilgovi, is this correct?

- File renamed to streamfilter.coffee
- StreamerFilter class renamed to StreamFilter
- Using dependency injection instead of "polluting" the window scope

- Changed '...' to '\u2026'
- Renamed it to elide
- Added split_length as a parameter

CSS adjustments in authentication flow and sidebar

- [B] ng-src instead of src
- [I] added date to the header view
- Header display redesign

 - [B] Make SockJSWrapper class usable
 - [B] Corrected user filter
 - [B] Username handled from template to angular
 - [I] Added url_values_from_document() to UrlAnalyzer class
 - [I] Streamer uses this new function to generate url data
 - Removed comment lines

Gets rid of the italic style on the collapsed-comment-ellipsis line, replaces with notched down opacity and font-size.

Gets rid of underline on un-clickable user names, replaces with bold font-weight and notched-up size.

On thread expand/contract boxes, changes outline style from dotted -> solid to get rid of weird visual artifacts at the corners.

Changes the font-family on the slow-validate errors and popups to the sansFontFamily to match the rest of the form.

Changes cursor CSS rule on the sidebar-expand button to 'w-resize' for consistency with the 'ew-resize' cursor on the expanded drag-handle.

- Add a response interceptor to the httpProvider so that the
  FlashProvider can unwrap the server responses, handle the flash
  messages, and pass along only the real result to the rest of the
  application.
- Accept JSON params to /app POSTs and clean up content negotiation.
- Use $resource to create an angular service for authentication.
- Encapsulate some global scope variables by using isolates and
  directives for the user picker and auth tabs.

Conflicts:
	h/resources.py

230 thread ordering