NB: this diff is best viewed with --ignore-whitespace
Distills crypto.js down to the hard cryptoey bones. It pulls from
webcrypto for aes and hmac, and from native client for curve25519 stuff
or potentially another object implementing the handful of needed
curve25519 functions.
Everything else formerly known as crypto, including session storage and
management, axolotl, etc.. is now protocol.js. The separation is not
quite perfect, but it's a big step.
nativeclient.js now enables talking to the native client module through
a high level interface as well as registering callbacks that will be
executed once the module is loaded. And it has tests!
Finally, this commit removes all references to the "testing_only"
object, preferring to run tests on textsecure.crypto instead.
We now correctly and opportunistically use the webcrypto API if
available, polyfilling if it's not detected. This change also includes a
layer of abstraction over the webcrypto interface so we no longer have
to deal with key-imports or algorithm names all over the place. Since we
no longer support AES-CTR, code outside this file can simply call
`textsecure.subtle.<encrypt|decrypt|sign>(key, data [, iv])`.
Sadly, we are not quite compliant with the WC3 webcrypto spec
due to our insistance on passing around key data in plain old
ArrayBuffers.
Also converted whitespace.
