Prettified CSS and Javascript, rearrange handlers.
style improvements
Incoming mail: don't panic on wrong address

Instead, if we have no user for a given To address, we simply
don't encrypt that mail.

For now, store it for easier debugging.

Eventually, we will probably change it to drop such mail.

(The SMTP server already notifies senders if the recipient
address is not found.)
Docs: fixed scroll bug, decoupled doc CSS from app CSS
Deployment: added Postfix config for email updates
Don't Panic!
cache notaries to sessionStorage
UI: Cache public key lookups for speed
UI: Added cipher- and plaintext caching
Made max incoming email size configurable. Default 15MB.

Note that this *bigger* than the max size that a user can currently send, or that we can store.

When we receive mail, we strip out all content types except text/plain, so a typical 15MB email will still be stored as a small bit of text.
Added hello@scramble.io to front page. Small JS cleanup.
Test Mailchimp signup page: /doc/signup.html

Real updates + blog coming soon
Merge pull request #2 from dcposch/master

Bring it up to date