Add wiki submenu to menu
Fix wiki search function,implement the wiki show
Add wiki document function
group chat tables

Basic tables for storing information pertaining to group chat.
These tables store user chat messages occurring within a chat
session. Individual chat settings for a user can also be stored.
fix spelling error in comment
Merge pull request #60 from matus85/master

Teacher View: reading all the homework assignments
Merge pull request #61 from aiolos404/master

Fix search, show function and implement document function
Merge pull request #62 from jjunk/master

Initial table setup for group chat