changed readme
Merge pull request #1 from ysshah/readme-B

changed readme
Merge pull request #2 from ysshah/readme-A

I also changed readme
Merge pull request #3 from ysshah/readme-A

Fixed login / logout.
enforced sign-in for users
Merge pull request #4 from ysshah/readme-B

enforced sign-in for users
Added login alert.