Added content-type declaration in index.html file
Corrected container width and hence horizontal centering of chat area
Removed some style declarations that have been become obsolete/not-required as part of the design rewrite.
Beautified the chatter list sidebar
Finished improved UI and its implemented all the basic features in it
Replaced cloud lightning image with a modified one to match the new background color
Security Fix: Added provision to strip html tags from user input