Prefetch dialog components from the communication_iframe

When the browser is idle, it will start fetching and caching the
dialog's Javascript, CSS and images. This works on IE9 and Firefox
(it's currently disabled in Chromium).

The trick is to make sure that the communication iframe is open
while the user is busy reading the RP's site. When using the
Observer API, this happens automatically at the end of the
navigator.id.watch() call.
Make use of new connect-cachify helper function
Specify the locale when prefetching the dialog stylesheet
Supress the "invalid json" error messages in the unit tests.

fixes #3290
Merge pull request #3292 from mozilla/issue_3290_qunit_console_messages

Supress the "invalid json" error messages in the unit tests.
Only emit prefetch tags in production mode

There are far too many JS/CSS files to prefetch in development
mode for prefetch to be effective (browsers seem to put a limit on
the number of files they will prefetch).
renderError will publish an error_screen event

these events are stored in the event stream

example: screen.error.establishing_relay
Merge pull request #3304 from seanmonstar/3302-kpi_unsupport_dialog_errors

renderError will publish an error_screen event
Fix the failing serverTime test.

It was not giving enough leeway for the increased number of onContextChange handlers.
Pass forceAuthentication as _experimental_forceAuthentication

fixes #3312
update to new cachify which will never poison caches, even if files on disk are changed without a server restart - issue #3315
Merge pull request #3316 from mozilla/kill-cache-poisioning

Mitigate accidental cache poisoning during deployment
document changes in 2013.04.26
bump dev to 2013.05.10
Merge pull request #3313 from mozilla/issue_3312_force_authentication

Pass forceAuthentication as _experimental_forceAuthentication
Merge pull request #3311 from mozilla/issue_3310_serverTime_failure

Fix the failing serverTime test.
Rebased dev and resolved conflicts in these files:

    resources/static/common/js/user.js
    resources/static/dialog/js/misc/helpers.js
    resources/static/dialog/js/modules/authenticate.js
    resources/static/test/cases/common/js/user.js

Conflicts:
	example/rp/index.html
	resources/static/dialog/js/misc/helpers.js
	resources/static/dialog/js/modules/dialog.js
Making forceIssuer optional on address_info and cert_key. Extracted withType.

Rewrote patch to work with latest primary-transition-ux patch on b2g tip.

Conflicts:
	resources/static/dialog/views/set_password.ejs

Conflicts:
	resources/static/dialog/js/modules/verify_primary_user.js
Missed adding new dbutils.js
i18n-abide requires named variables to be replaced to end with `s`