sjcl.random.randomWords with missing paranoia argument throws error

`crypt.createMaster()` and `crypt.createSecret()` throw the following error, because they call `sjcl.random.randomWords(nWords, paranoia)` without a `paranoia` argument.

```
/Users/luke/code/ripple/node_modules/ripple-lib/build/sjcl.js:1744
      throw new sjcl.exception.notReady("generator isn't seeded");
            ^
NOT READY: generator isn't seeded
```

This throws during VaultClient.register(), and probably elsewhere.

This pull request sets paranoia to 0 in both `crypt.createMaster()` and `crypt.createSecret()`.