Handle blank password in basic auth.

[diversario]

Fixes #681.

[nylen]

My only issue with this is that now options.auth.pass will behave differently from options.auth.password. However, there's already a similar issue with options.auth.user vs options.auth.username, so I'm not sure how much this matters. @mikeal, care to comment?

[diversario]

@nylen that's true. Are password and username legacy options? If so it would make sense to map them on the shorter fields, if they're present. I can't imagine that people use both at the same time. So, something like

if (Object.prototype.hasOwnProperty.call(options.auth, 'username')) options.auth.user = options.auth.username
if (Object.prototype.hasOwnProperty.call(options.auth, 'password')) options.auth.pass = options.auth.password

No need to care about legacy options after this.

[nylen]

I agree. Personally I would have gone with typeof options.auth.username != 'undefined', but I'd merge it either way.

I put the alias names in there so that you could use either variant, without having to refer back to the docs to remember the naming convention.

[diversario]

How about that? Last commit?

[nylen]

Much cleaner, thanks!

[mikeal]

for some reason Travis is complaining about tests failing with optionals enabled/disbled or something. i have no idea what that means.

[diversario]

Tests pass locally (for me, at least).

[mikeal]

me too :)