Add salt argument to compare/compareSync

[andrewjmead]

First, great library. Thanks.

I'm using a salt for my passwords and found it odd that when hashing my password there was an argument for the salt, but when comparing my passwords there is not. I was assuming the syntax would be something like:

var isMatch = bcrypt.hashSync(password, salt, hashedPassword);

Is this something you would consider doing or consider accepting a PR for?

[ncb000gt]

bcrypt salts are stored as a part of the hash and are therefore not required in the comparison as a separate parameter. :)