Changes after code review

Description

1.Team name problem is resolved

2.Team members name are aligned with "Team members"

3.Use reject instead of remove in "showdetails.php"

4.Permission link problems are resolved for addrem.php and approval.php

5.Error message comes in one line

6.Change the name index.html to index.php in every page's home button

7.If user is logged in it will show welcome message in home page and logout option

8. After logging out it will redirect to home page instead of login.php