Migrate from bcrypt-nodejs to bcrypt

[ghost]

Closes #44

[msftclas]

All CLA requirements met.

[ghost]

Added commits in reference to #285.

[peterblazejewicz]

These are three different topics here:

1. chai - seems no brainer, it seems to be left-over from previous implementation detail
2. bcrypt - this was already discussed on project and raised. In all previous occasions PR owners decided to not update the library, as the bcrypt rquires native dependencies that are not always available for specific installation. E.g. see comment:
   Update bcrypt & node-sass #253 (comment)
3. model definition - that's not brainer either, OK.

If you could split this PR into focused ones, it would be better to grasp the topics. (make three branches, cherry-pick your commits to topic branch, push pr), it would help

[bluepuma77]

I tested TypeScript-Node-Starter for the first time today and stumbled upon this:

npm WARN deprecated [email protected]: bcrypt-nodejs is no longer actively maintained. Please use bcrypt or bcryptjs. See https://github.com/kelektiv/node.bcrypt.js/wiki/bcrypt-vs-brypt.js to learn more about these two options

For newcomers it might look like your project is not maintained when using deprecated libraries.