Add decryption of the double encryption and T3 signing

* Change cashout2 page layout and add more Crypto-JS script
  sources as well as using the rollups instead of components ones.
* Cleanup source code of prep and sign pages to have more consistent
  style and variable namings.
* Add base64 encoding of the oracle RSA privkey sent out for T3.
* Add RSA decryption of the encrypted event key
  (with giver/taker key) to get AES key for further decryption.
* Add AES decryption code using Crypto-JS to get to the second
  encryption
* Add base64 encoding of the oracle RSA key to avoid PEM newline
  issues in JS.
* Change RSA encryption padding from PKCS#1 to OAEP.
* Change EC test key generation in Mw to generate uncompressed
  mainnet keys in WIF format.
* Add T3 signatures submit requests to cashout2 page which is
  called after successful decryption of the encrypted event key.