fix. ensure that password passed to generate_password_hash is a string.
mod. refactor API user to determine users registration status on init.  Also, get now takes in user/pass credentials and returns a boolean
mod. refactor auth portion of session management.  Add method to perform auth with salted hashes
mod. simplify and make consistent login view with new APIUser class.
Merge pull request #15 from rfaulkner/master

Fix authentication using salted passwords