Function for generating a backed identity assertion

Includes the browserid bundle from jwcrypto, a jasmine test, and a test
page.
Add test for predefined backed id assert.

Makes function have extra optional arguments for setting the expiration
time and creation time.
Add backed identity assertion files to subtemplate.
Fix PGP subtemplate typos. Rebuild new.html.
PGP: Move jwcrypto bundle to correct directory.
Remove exp, iat options from identity.

Make the test something more reasonable than a direct cert comparison.
Remove jwcrypto.html now that test has been written.
Add notes on things that still need to happen.
Add methods to PersonaId.

sign, verify, bundle, verifyPayload, and extractPubkey all added for
dealing with the payload to/from a directory provider.

Test also updated with reference to PersonaId.
Add basic test outlines for PersonaId.
Remove 'generateBackedIdentityAssertion' function
Fix reference to PersonaId method, add TODO.
Fix typos in PersonaId

Added a TODO, along with removing an un-needed function call.
Use jwcrypto 0.4.5, not anything newer.
Add tests for PersonaId.{sign, verify}.
Change 'self' to 'this' in PersonaId.

Too much python...

Fixed a minor whitespace issue.
Fixed callback params for 'sign' in 'bundle'.
Replace assertion in tests, add test for bundle.
Fix all the indenting, remove TODO in identity.js
Fix whitespace in test/identity.js.
Add tests for verifyPayload, extractPubkey

Fixes methods in the process.
Fix minor whitespace issues.