Adding basic authentication

Database table: users

In the design #3 I chose the name authentication, however due to CakePHP naming conventions it was much quicker just to use users instead

url: /users/[action]

actions:
add - Allows you to add a new user
index - not implemented yet
view - not implemented yet
login - authenticates the user and creates a session
logout - ends user session
edit - not implemented yet
delete - not implemented yet

Need to work on access control list to control the authorization before I can implement the settings panel. See issues.

Added CSS, JS and fonts from design-service-provider branch. Set up a basic theme.

Installer needs to set up an admin user.
Merge branch 'build' of https://github.com/danieljsamson/tempus into build