1.0.0

[jonathanong]

aside from the other issues listed:

• options default to Cookies([options]). this means that doing .set() without any options doesn't mean to signed: false, and .set() with an empty option doesn't default to signed: !!this.keys. this is super confusing.
• overwrite defaults to true

[dead-horse]

any progress? /cc @jonathanong @dougwilson