Fix two recent regressions with authentication. The first is the lack
of form error reporting. The second is the issue that ongoing highlight
mode switches and edits don't proceed after login.

- Unify all the interceptors related to sessioning. The interceptor for
  flash messages, csrf, and extracting the model from the session view
  responses is now all in session.coffee. This is better because it
  means other requests that don't return data in the same format aren't
  processed by these interceptors. It also makes it clearer which data
  the interceptors are processing; the CSRF interceptor may have been
  broken because the flash interceptor was discarding the data outside
  the model object.
- The CSRF interceptor was also not returning a rejected promise on
  errors. This mistake caused the errors not to be propagated to the
  Auth form controller. Fix #1266.
- The interaction between the Auth controller, session model changes,
  and scope resets is improved. The timeouts on the auth sheet are
  fixed so that they don't lose the ongoing mode switches and edits
  when the sheet is closed. Fix #1214.

Re-jig the integration tests 

This is now used as the primary platform for functional tests until
we can get Sauce Labs running reliably.

Fix failing annotator login test on OSX

Without this change, clicking highlight mode and then dismissing the
authentication without logging in will make it so that one must click
it twice to trigger the behavior again.

Make "make clean" compatible with OSX

Until we start packaging and releasing a version with pre-built
assets, these are needed at runtime.

Add Java installation instructions to INSTALL.OSX.rst

Manage frontend dependencies with npm

This allows us to install all but compass locally in the project rather
than relying on global executables.

Part of #1231

Had inconsistencies with tag and tags.
Unwanted console.log was also removed

Fixes #1267

It's not reasonable to be shipping this here. We should be including
the source in the source map files or even including the source map
inline in the source map comment. The Annotator master branch does
this. For now, I'm putting the pressure on here. No source maps until
we get off this damn fork.

Fix #1265

Moved to hypothesis/firefox-addon

Fix mappings for tags field

1237 assets combination

The tag-it library is now configured to allow spaces.
However by default the window.open() function converts
the space characters in the query part of the uri to +
The streamsearch controller is now handling this conversion too.

Fixes #1254

For now. Soon we will merge this with the page search and make things
much more similar.

Make a directive for visualsearch that eases integration by taking
care of digest cycles and providing declarative binding for events.

Remove the state tracking with inSearch and will_search and replace
it by reflect the search directly in the query string.

Factor out a socket factory into a service and send the client ID only
before the first message. Configure the client ID and this service in a
new module, h.socket. Fix the base URI to end in a slash and to be the
root URL of the server.

Fix the border poking out under the active tab.

Rename it as session, since that's closer to what it's really about.

The auth drop down in the top right of the sidebar was showing a border
on the "top" entry because the first one was hidden.

Remove CSS which is redundant with visualsearch CSS; remove CSS which
serves no purpose or which is unused; place the search container inside
the inner div of the topbar; and just neaten things up.

Firefox Add-on; far easier than expected

After this bugfix, we are now storing the canonical URLs
in the URI field of the created annotations.

This update fixes the XPath creation, so that our highlights won't leak into them.

Some browsers seem to care about this. Close #1241.

This reverts commit 4eb0de8ea0de8098e2771c8a276d75434f2c99f6.

This commit removes the dtm plugin and all dtm dependent plugins from
the guest.coffee and introduces a dtm parameter inside the embed.txt
If this parameter is true (by default  it is) it loads the
DomTextMapper, TextPosition, FuzzyTextAnchors, PDF plugins.

Fixes #1233

When always on highlights and the highlighter mode were introduced in
ddf17189fbf2d428b21fd31065a1c2d2bc6ab08b the beforeAnnotationCreated
event was not fired in the guest frame. Instead, a special inject call
was added to the bridge to send the annotation and the event fired in
the iframe first. Later, when I removed this, I added the event after
the call to setupAnnotation.

The change in 3613c7d91682a438b1d243b9573cb941b26cdc43 uses the
annotationsLoaded event to notify listeners when highlights change as a
result of realizing anchors. This presents a problem because the bridge
ignores the beforeAnnotationCreated event for annotations that have
already been tagged by the bridge, but this load event causes the new
highlight to be tagged and serialized.

Move the beforeAnnotationCreated event to before the setupAnnotation
call, which is the order of things in non-highlighter mode, so that
the event is properly propagated to the sidebar iframe.

Close #1240