Changing auth.basic to regular auth.

Routes: Added routes for /login (get), /login (post), and /logout

HomeController: Added actions for showLogin, doLogin, and doLogout. showLogin loads login form view, doLogin attempts auth, doLogout just logs current auth user out.

PostsController: changed auth.basic to auth.

views/index: basic domain index page. need to flesh out.

views/login: basic user auth form--email and password credentials accepted as input.

layouts/master: changed css and js to asset links. added nav link to login/logout if guest/auth-user