Make the password optional

[john-light]

I would like to make adding a password to an account optional.

Maybe there are some accounts that I use exclusively for testnet, or low value, and having a password isn't worth the effort on these accounts. Or maybe I simply don't care about putting a password at all, because I rely on my OS Home password for securing access to my computer. Whatever the reason, I would like the choice of whether to set a password or not.