Switches to object config argument syntax over mutli args

[mjrussell]

Resolves #8

Allows for far more variety of config options and lets the user set the fields they really want. Previously if the user wanted allowRedirectBack to be false, they had to specify predicate even if they wanted the default behavior.

const UserIsAuthenticated = UserAuthWrapper(state => state.user)('/login', 'UserIsAuthenticated')

becomes

const UserIsAuthenticated = UserAuthWrapper({
  authSelector: state => state.user,
  wrapperDisplayName: 'UserIsAuthenticated'
})

Preserves a backwards (deprecated) compatible version.

Updated tests, README, and examples.