extract hard-coded credentials from both client and server
client: clear obsolete message
js: separate sections with comments
client: rename func 'submit' to 'authenticate'
server: serve static content from dir 'public'
client: print token to console
server: add explanation to middlewares
server: create obj 'consts'
server: create utils funcs; use 'consts' for constants
server: add user 'admin'
client: split `$scope.user` in two separate models
client: remove hard-coded user credentials
client: move func 'url_base64_decode' into 'myUtils'
client: add func to split JWTs