Create README.md

change this file as needed
Merge pull request #1 from COMP7081-Group5/callum

Callum
removed gson include
Merge branch 'master' of https://github.com/COMP7081-Group5/chatClient
uncommented client login function, adding database imports to server.java
add fucntion that admin can add a new user.
Merge pull request #2 from COMP7081-Group5/ben

add fucntion that admin can add a new user.
modify ChatMessage.java