Security chapter

[damienbod]

I think a security chapter would be useful:

https://damienbod.com/2016/03/02/angular2-openid-connect-implicit-flow-with-identityserver4/

https://github.com/michaeloryl/angular2-bootstrap4-oauth2-webpack

http://www.softwarearchitekt.at/post/2016/07/03/authentication-in-angular-2-with-oauth2-oidc-and-guards-for-the-newest-new-router-english-version.aspx

https://github.com/auth0-blog/angular2-authentication-sample

Should I create a PR? I'll add it at the end, ok?

greetings Damien

[PatrickJS]

good idea, can you make a PR

[damienbod]

OK

[damienbod]

pull request: #126