Implement pseudoRandomBytes.

Provide the same interface as rng, but fallback to pseudoRandomBytes on node.
Add pseudoRandomBytes to random-bytes test suite.
Remove extra new Buffer in randomBytes functions.
publicEncrypt and privateDecrypt
upgrade aes to check padding
upgrade browserify-sign to handle dsa signatures
Merge branch 'dsa-sign' of https://github.com/calvinmetcalf/crypto-browserify
Merge branch 'public-encrypt' of https://github.com/calvinmetcalf/crypto-browserify

Conflicts:
  package.json
Merge branch 'add-pseudoRandomBytes' of https://github.com/plediii/crypto-browserify
3.7.0
Merge with master.