Do not generate a silent assertion for an address in a transition state. Update backend to correctly mark addresses as "secondary" upon verification.

* When calling /wsapi/complete_reset.js or /wsapi/complete_transition.js, immediately flip the type of the email address to "secondary"
* Add explanation of silent assertions.

fixes #3515
Add Selenium tests to check for transition states.
Add backend tests for transition_no_password and transition_to_secondary cases to ensure email type is set to secondary and state changed to known.
Add a transition-to-secondary-forgot-password Selenium test.

This is for a user who has to transition to a secondary but forgot their password.
When the user cancels from the "primary_offline" state, reset the caches so the user can try the address again.

Fixes #3155
on posix, add a sigint handler to dump state so far
Merge pull request #3565 from mozilla/issue_3155-address-lookup-fail

When the user cancels from the "primary_offline" state, reset the caches so the user can try the address again.
Merge pull request #3545 from mozilla/issue_3515-silent-assertions

Do not generate a silent assertion for an address in a transition state.
experimenting with branding.
Start to clean up the HTML and CSS to match the mocks.
add the persona watermark in the footer
Place the arrow as a background image on #signIn instead of having its own container. It makes the transition smoother.
Reset background color to something neutral.
First pass at backgroundColor support.
Fix jslint warnings reported by Travis.
Close the stupid string.
And remove unreachable return statement.
Fix primaries on FirefoxOS
Styling cleanup. Add bg color inputs to example RP.

* Make sure colors look correct on mobile
* In desktop, add a box-shadow to the right hand side of the user area to match the arrow.
* Remove grain.png from the message screens. It's ugly with the new stylings.
* Add bg color and RP name inputs to example RP.
Extract validation and color derivation into separate functions.