Basics

The following has been completed:
- Login/Logout
- Send/Receive messages
- Switch between chat topics

Functionality still to be done:
- Create/Delete topics
- View online users in topic
- Manage users (admin function only)
- Press Enter to send message
- CSS improvements
-- responsive design for mobi
-- general improvements
-- cross browser testing

functions/secret.php not in repo for security reasons. Contains a
defined constant for firebase secret key.
Local database dump can be found in bizchat.sql.

Test login details:
email: danny@dannynochumsohn.com
password: 12345